Orthodontic articles prepared using a polycarbonate diol, and methods of making same

ABSTRACT

The present disclosure provides an orthodontic article including the reaction product of the photopolymerizable composition. The photopolymerizable composition includes i) a monofunctional (meth)acrylate monomer whose cured homopolymer has a glass transition temperature of 90 degrees Celsius or greater; ii) a photoinitiator; and iii) a polymerization reaction product of components. The components include 1) an isocyanate; 2) a (meth)acrylate mono-ol; 3) a polycarbonate diol; and 4) a catalyst. Further, the present disclosure provides a method of making an orthodontic article. The method includes obtaining a photopolymerizable composition and selectively curing the photopolymerizable composition to form an orthodontic article. Further, methods are provided, including receiving, by a manufacturing device having one or more processors, a digital object comprising data specifying an orthodontic article; and generating, with the manufacturing device by an additive manufacturing process, the orthodontic article based on the digital object. A system is also provided, including a display that displays a 3D model of an orthodontic article; and one or more processors that, in response to the 3D model selected by a user, cause a 3D printer to create a physical object of an orthodontic article.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.17/042,384, filed Sep. 28, 2020, which is a national stage filing under35 U.S.C. 371 of PCT/US2019/033252, filed May 21, 2019, which claims thebenefit of U.S. Application No. 62/692,456, filed Jun. 29, 2018; U.S.Application No. 62/736,031, filed Sep. 25, 2018; and U.S. ApplicationNo. 62/769,421, filed Nov. 19, 2018, the disclosures of which areincorporated by reference in their entireties herein.

TECHNICAL FIELD

The present disclosure broadly relates to orthodontic articles andmethods of making the orthodontic articles, such as additivemanufacturing methods.

BACKGROUND

The use of stereolithography and inkjet printing to producethree-dimensional articles has been known for a relatively long time,and these processes are generally known as methods of so called 3Dprinting (or additive manufacturing). In vat polymerization techniques(of which stereolithography is one type), the desired 3D article isbuilt up from a liquid, curable composition with the aid of a recurring,alternating sequence of two steps: in the first step, a layer of theliquid, curable composition, one boundary of which is the surface of thecomposition, is cured with the aid of appropriate radiation within asurface region which corresponds to the desired cross-sectional area ofthe shaped article to be formed, at the height of this layer, and in thesecond step, the cured layer is covered with a new layer of the liquid,curable composition, and the sequence of steps is repeated until aso-called green body (i.e., gelled article) of the desired shape isfinished. This green body is often not yet fully cured and must,usually, be subjected to post-curing. The mechanical strength of thegreen body immediately after curing, otherwise known as green strength,is relevant to further processing of the printed articles.

Other 3D printing techniques use inks that are jetted through a printhead as a liquid to form various three-dimensional articles. Inoperation, the print head may deposit curable photopolymers in alayer-by-layer fashion. Some jet printers deposit a polymer inconjunction with a support material or a bonding agent. In someinstances, the build material is solid at ambient temperatures andconverts to liquid at elevated jetting temperatures. In other instances,the build material is liquid at ambient temperatures.

SUMMARY

Existing printable/polymerizable resins tend to be too brittle (e.g.,low elongation, short-chain crosslinked bonds, thermoset composition,and/or high glass transition temperature) for a resilient oral appliancesuch as an aligner. An aligner or other appliance prepared from suchresins could easily break in the patient's mouth during treatment,creating material fragments that may abrade or puncture exposed tissueor be swallowed. These fractures at the very least interrupt treatmentand could have serious health consequences for the patient. Thus, thereis a need for curable liquid resin compositions that are tailored andwell suited for creation of resilient articles using 3D printing (e.g.,additive manufacturing) method. Preferably, curable liquid resincompositions to be used in the vat polymerization 3D printing processhave low viscosity, a proper curing rate, and excellent mechanicalproperties in the final cured article. In contrast, compositions forinkjet printing processes need to be much lower viscosity to be able tobe jetted through nozzles, which is not the case for most vatpolymerization resins.

In a first aspect, an orthodontic article is provided. The orthodonticarticle includes a) a polymerized reaction product of aphotopolymerizable composition. The photopolymerizable compositionincludes i) a monofunctional (meth)acrylate monomer whose curedhomopolymer has a T_(g) of 90° C. or greater; ii) a photoinitiator; andiii) a polymerization reaction product of components. The components ofiii) include 1) an isocyanate; 2) a (meth)acrylate mono-ol; apolycarbonate diol of Formula (I): H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and3) a catalyst. Each of R₁ in each (O—R₁—O—C(═O)) repeat unit and each R₂are independently an aliphatic, cycloaliphatic, oraliphatic/cycloaliphatic alkylene group and an average number of carbonatoms in a combination of all the R₁ and R₂ groups is 4 to 10, and m is(an integer of) 2 to 23. The polymerized reaction product of thephotopolymerizable composition has a shape of the orthodontic article.

In a second aspect, a method of making an orthodontic article isprovided. The method includes a) obtaining a photopolymerizablecomposition according to the first aspect; b) selectively curing thephotopolymerizable composition; and c) repeating steps a) and b) to formmultiple layers and create the orthodontic article.

In a third aspect, a non-transitory machine readable medium is provided.The non-transitory machine readable medium includes data representing athree-dimensional model of an orthodontic article, when accessed by oneor more processors interfacing with a 3D printer, causes the 3D printerto create an orthodontic article comprising a reaction product of aphotopolymerizable composition according to the first aspect.

In a fourth aspect, a method is provided. The method includes a)retrieving, from a non-transitory machine readable medium, datarepresenting a 3D model of an article; b) executing, by one or moreprocessors, a 3D printing application interfacing with a manufacturingdevice using the data; and c) generating, by the manufacturing device, aphysical object of the orthodontic article. The orthodontic articleincludes a reaction product of a photopolymerizable compositionaccording to the first aspect.

In a fifth aspect, another method is provided. The method includes a)receiving, by a manufacturing device having one or more processors, adigital object comprising data specifying a plurality of layers of anorthodontic article; and b) generating, with the manufacturing device byan additive manufacturing process, the orthodontic article based on thedigital object. The orthodontic article includes a reaction product of aphotopolymerizable composition according to the first aspect.

In a sixth aspect, a system is provided. The system includes a) adisplay that displays a 3D model of an orthodontic article; and b) oneor more processors that, in response to the 3D model selected by a user,cause a 3D printer to create a physical object of an orthodonticarticle. The orthodontic article includes a reaction product of aphotopolymerizable composition.

In a seventh aspect, a compound is provided. The compound is of Formula(V):

The compound of the seventh aspect can advantageously be used as a UVabsorber in orthodontic articles and methods according to the firstthrough fifth aspects.

Clear tray aligners and tensile bars made according to at least certainembodiments of this disclosure were found to show low brittleness, goodresistance to water, and good toughness.

The above summary of the present disclosure is not intended to describeeach disclosed embodiment or every implementation of the presentdisclosure. The description that follows more particularly exemplifiesillustrative embodiments. In several places throughout the application,guidance is provided through lists of examples, which examples can beused in various combinations. In each instance, the recited list servesonly as a representative group and should not be interpreted as anexclusive list.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of a process for building an article using thephotopolymerizable compositions disclosed herein.

FIG. 2 is a generalized schematic of a stereolithography apparatus.

FIG. 3 is an isometric view of a printed clear tray aligner, accordingto one embodiment of the present disclosure.

FIG. 4 is a flowchart of a process for manufacturing a printedorthodontic appliance according to the present disclosure.

FIG. 5 is a generalized schematic of an apparatus in which radiation isdirected through a container.

FIG. 6 is a block diagram of a generalized system 600 for additivemanufacturing of an article.

FIG. 7 is a block diagram of a generalized manufacturing process for anarticle.

FIG. 8 is a high-level flow chart of an exemplary article manufacturingprocess.

FIG. 9 is a high-level flow chart of an exemplary article additivemanufacturing process.

FIG. 10 is a schematic front view of an exemplary computing device 1000.

While the above-identified figures set forth several embodiments of thedisclosure other embodiments are also contemplated, as noted in thedescription. The figures are not necessarily drawn to scale. In allcases, this disclosure presents the invention by way of representationand not limitation. It should be understood that numerous othermodifications and embodiments can be devised by those skilled in theart, which fall within the scope and spirit of the principles of theinvention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

As used herein, “aliphatic group” means a saturated or unsaturatedlinear, branched, or cyclic hydrocarbon group. This term is used toencompass alkyl, alkenyl, and alkynyl groups, for example.

As used herein, “alkyl” means a linear or branched, cyclic or acyclic,saturated monovalent hydrocarbon having from one to thirty-two carbonatoms, e.g., methyl, ethyl, 1-propyl, 2-propyl, pentyl, and the like.

As used herein, “alkylene” means a linear saturated divalent hydrocarbonhaving from one to twelve carbon atoms or a branched saturated divalenthydrocarbon radical having from three to twelve carbon atoms, e.g.,methylene, ethylene, propylene, 2-methylpropylene, pentylene, hexylene,and the like.

As used herein, “alkenyl” refers to a monovalent linear or branchedunsaturated aliphatic group with one or more carbon-carbon double bonds,e.g., vinyl. Unless otherwise indicated, the alkenyl groups typicallycontain from one to twenty carbon atoms.

As used herein, the term “arylene” refers to a divalent group that iscarbocyclic and aromatic. The group has one to five rings that areconnected, fused, or combinations thereof. The other rings can bearomatic, non-aromatic, or combinations thereof. In some embodiments,the arylene group has up to 5 rings, up to 4 rings, up to 3 rings, up to2 rings, or one aromatic ring. For example, the arylene group can bephenylene.

As used herein, “aralkylene” refers to a divalent group that is analkylene group substituted with an aryl group or an alkylene groupattached to an arylene group. The term “alkarylene” refers to a divalentgroup that is an arylene group substituted with an alkyl group or anarylene group attached to an alkylene group. Unless otherwise indicated,for both groups, the alkyl or alkylene portion typically has from 1 to20 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4carbon atoms. Unless otherwise indicated, for both groups, the aryl orarylene portion typically has from 6 to 20 carbon atoms, 6 to 18 carbonatoms, 6 to 16 carbon atoms, 6 to 12 carbon atoms, or 6 to 10 carbonatoms.

As used herein, the term “essentially free” in the context of acomposition being essentially free of a component, refers to acomposition containing less than 1% by weight (wt. %), 0.5 wt. % orless, 0.25 wt. % or less, 0.1 wt. % or less, 0.05 wt. % or less, 0.001wt. % or less, or 0.0001 wt. % or less of the component, based on thetotal weight of the composition.

As used herein, the term “glass transition temperature” (T_(g)), of apolymer refers to the transition of a polymer from a glassy state to arubbery state and can be measured using Differential ScanningCalorimetry (DSC), such as at a heating rate of 10° C. per minute in anitrogen stream. When the T_(g) of a monomer is mentioned, it is theT_(g) of a homopolymer of that monomer. The homopolymer must besufficiently high molecular weight such that the T_(g) reaches alimiting value, as it is generally appreciated that a T_(g) of ahomopolymer will increase with increasing molecular weight to a limitingvalue. The homopolymer is also understood to be substantially free ofmoisture, residual monomer, solvents, and other contaminants that mayaffect the T_(g). A suitable DSC method and mode of analysis is asdescribed in Matsumoto, A. et. al., J. Polym. Sci. A., Polym. Chem.1993, 31, 2531-2539.

As used herein, the terms “hardenable” refers to a material that can becured or solidified, e.g., by heating to remove solvent, heating tocause polymerization, chemical crosslinking, radiation-inducedpolymerization or crosslinking, or the like.

As used herein, “curing” means the hardening or partial hardening of acomposition by any mechanism, e.g., by heat, light, radiation, e-beam,microwave, chemical reaction, or combinations thereof.

As used herein, “cured” refers to a material or composition that hasbeen hardened or partially hardened (e.g., polymerized or crosslinked)by curing.

As used herein, “integral” refers to being made at the same time orbeing incapable of being separated without damaging one or more of the(integral) parts.

As used herein, the term “(meth)acrylate” is a shorthand reference toacrylate, methacrylate, or combinations thereof, “(meth)acrylic” is ashorthand reference to acrylic, methacrylic, or combinations thereof,and “(meth)acryl” is a shorthand reference to acryl and methacrylgroups. “Acryl” refers to derivatives of acrylic acid, such asacrylates, methacrylates, acrylamides, and methacrylamides. By“(meth)acryl” is meant a monomer or oligomer having at least one acrylor methacryl groups, and linked by an aliphatic segment if containingtwo or more groups. As used herein, “(meth)acrylate-functionalcompounds” are compounds that include, among other things, a(meth)acrylate moiety.

As used herein, “polymerizable composition” means a hardenablecomposition that can undergo polymerization upon initiation (e.g.,free-radical polymerization initiation). Typically, prior topolymerization (e.g., hardening), the polymerizable composition has aviscosity profile consistent with the requirements and parameters of oneor more 3D printing systems. In some embodiments, for instance,hardening comprises irradiating with actinic radiation having sufficientenergy to initiate a polymerization or cross-linking reaction. Forinstance, in some embodiments, ultraviolet (UV) radiation, e-beamradiation, or both, can be used. When actinic radiation can be used, thepolymerizable composition is referred to as a “photopolymerizablecomposition”.

As used herein, a “resin” contains all polymerizable components(monomers, oligomers and/or polymers) being present in a hardenablecomposition. The resin may contain only one polymerizable componentcompound or a mixture of different polymerizable compounds.

As used herein, the “residue of a diisocyanate”, is the structure of thediisocyanate after the —NCO groups are removed. For example,1,6-hexamethylene diisocyanate has the structure OCN—(CH₂)₆—NCO, and itsresidue, Rai, after removal of the isocyanate groups is —(CH₂)₆—.

As used herein, the “residue of a polycarbonate polyol”, is thestructure of the polycarbonate polyol after the —OH groups are removed.For example, a polycarbonate diol having the structureH(O—R₁—O—C(═O))_(m)—O—R₂—OH, has a residue, R_(dOH), after removal ofthe end —OH groups, of —R₁—O—C(═O)—(O—R₁—O—C(═O))_(m-1)—O—R₂—, whereineach R₁ in each repeat unit and R₂ is independently an aliphatic,cycloaliphatic, or aliphatic/cycloaliphatic alkylene group and m is 2 to23. Examples of R₁ and R₂ groups include —CH₂—CH₂—CH(CH₃)—CH₂—CH₂—,—CH₂—C(CH₃)₂—CH₂—, —(CH₂)₆—, —(CH₂)₉—, and —(CH₂)₁₀—.

As used herein, “thermoplastic” refers to a polymer that flows whenheated sufficiently above its glass transition point and become solidwhen cooled.

As used herein, “thermoset” refers to a polymer that permanently setsupon curing and does not flow upon subsequent heating. Thermosetpolymers are typically crosslinked polymers.

As used herein, “occlusal” means in a direction toward the outer tips ofthe patient's teeth; “facial” means in a direction toward the patient'slips or cheeks; and “lingual” means in a direction toward the patient'stongue.

The words “preferred” and “preferably” refer to embodiments of thedisclosure that may afford certain benefits, under certaincircumstances. However, other embodiments may also be preferred, underthe same or other circumstances. Furthermore, the recitation of one ormore preferred embodiments does not imply that other embodiments are notuseful, and is not intended to exclude other embodiments from the scopeof the disclosure.

In this application, terms such as “a”, “an”, and “the” are not intendedto refer to only a singular entity, but include the general class ofwhich a specific example may be used for illustration. The terms “a”,“an”, and “the” are used interchangeably with the term “at least one.”The phrases “at least one of” and “comprises at least one of” followedby a list refers to any one of the items in the list and any combinationof two or more items in the list.

As used herein, the term “or” is generally employed in its usual senseincluding “and/or” unless the content clearly dictates otherwise.

The term “and/or” means one or all of the listed elements or acombination of any two or more of the listed elements.

Also herein, all numbers are assumed to be modified by the term “about”and preferably by the term “exactly.” As used herein in connection witha measured quantity, the term “about” refers to that variation in themeasured quantity as would be expected by the skilled artisan making themeasurement and exercising a level of care commensurate with theobjective of the measurement and the precision of the measuringequipment used. Also herein, the recitations of numerical ranges byendpoints include all numbers subsumed within that range as well as theendpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

As used herein as a modifier to a property or attribute, the term“generally”, unless otherwise specifically defined, means that theproperty or attribute would be readily recognizable by a person ofordinary skill but without requiring absolute precision or a perfectmatch (e.g., within +/−20% for quantifiable properties). The term“substantially”, unless otherwise specifically defined, means to a highdegree of approximation (e.g., within +/−10% for quantifiableproperties) but again without requiring absolute precision or a perfectmatch. Terms such as same, equal, uniform, constant, strictly, and thelike, are understood to be within the usual tolerances or measuringerror applicable to the particular circumstance rather than requiringabsolute precision or a perfect match.

In a first aspect, the present disclosure provides an orthodonticarticle. The orthodontic article includes:

-   -   a) a polymerized reaction product of a photopolymerizable        composition comprising:        -   i) a monofunctional (meth)acrylate monomer whose cured            homopolymer has a T_(g) of 90° C. or greater;        -   ii) a photoinitiator; and        -   iii) a polymerization reaction product of components, the            components comprising:            -   1) an isocyanate;            -   2) a (meth)acrylate mono-ol;            -   3) a polycarbonate diol of Formula (I):

H(O—R₁—O—C(═O))_(m)—O—R₂—OH  (I)

-   -   -   -   -   wherein each of R₁ in each (O—R₁—O—C(═O)) repeat                    unit and each R₂ are independently an aliphatic,                    cycloaliphatic, or                -   aliphatic/cycloaliphatic alkylene group and an                    average number of carbon atoms in a combination of                    all the R₁ and R₂ groups is 4 to 10, and m is 2 to                    23; and

            -   4) a catalyst;

    -   wherein the polymerized reaction product has a shape of the        orthodontic article.

The components (i) through (iii) (and 1) through 4)) are discussed indetail below.

Monofunctional (Meth)Acrylate Monomer

In any embodiment, the photopolymerizable composition comprises amonofunctional (meth)acrylate monomer having a high glass transitiontemperature (T_(g)), i.e., whose cured homopolymer has a T_(g) of 90° C.or greater. In some embodiments, a monofunctional (meth)acrylate monomeris present whose cured homopolymer has a T_(g) of 100° C. or greater,110° C. or greater, 120° C. or greater, 125° C. or greater, 130° C. orgreater, 135° C. or greater, 140° C. or greater, 145° C. or greater,150° C. or greater, 155° C. or greater, 160° C. or greater, 165° C. orgreater, 170° C. or greater, 175° C. or greater, 180° C. or greater,185° C. or greater, 190° C. or greater, or even 195° C. or greater. Inselect embodiments, a monofunctional (meth)acrylate monomer is presentwhose cured homopolymer has a T_(g) of 150° C. or greater, 170° C. orgreater, or 180° C. or greater. The T_(g) of the homopolymer of themonofunctional (meth)acrylate monomer is typically no greater than about260° C. For example, 1-adamantyl methacrylate decomposes at about 260°C. In some embodiments, the T_(g) of the homopolymer of themonofunctional (meth)acrylate monomer is no greater than 255° C., 250°C., 245° C., 240° C., 235° C., 230° C., 225° C., 220° C., 215° C., 210°C., 205° C. or 200° C. The inclusion of one or more monofunctional(meth)acrylate monomers whose cured homopolymer has a T_(g) of 90° C. orgreater in a photopolymerizable composition contributes to increasingthe relaxation modulus of a photopolymerization reaction product of thecomposition as measured after soaking in deionized water. Often, theT_(g) of a homopolymer of a monomer can be found in the literature, suchas in Table 1 below. Table 1 includes the reported T_(g) of thehomopolymer of a number of monofunctional (meth)acrylate monomers andthe literature source of the reported T_(g).

In some embodiments, the monofunctional (meth)acrylate monomer comprisesa cycloaliphatic monofunctional (meth)acrylate. Suitable monofunctional(meth)acrylate monomers include for instance and without limitation,dicyclopentadienyl acrylate, dicyclopentanyl acrylate,dimethyl-1-adamantyl acrylate, cyclohexyl methacrylate, butylmethacrylate (e.g., tert-butyl methacrylate), 3,3,5-trimethylcyclohexylmethacrylate, butyl-cyclohexylmethacrylate (e.g.,cis-4-tert-butyl-cyclohexylmethacrylate, 73/27trans/cis-4-tert-butylcyclohexylmethacrylate, ortrans-4-tert-butylcyclohexyl methacrylate), 2-decahydronapthylmethacrylate, 1-adamantyl acrylate, dicyclopentadienyl methacrylate,dicyclopentanyl methacrylate, isobornyl methacrylate (e.g.,d,l-isobornyl methacrylate), dimethyl-1-adamantyl methacrylate, bornylmethacrylate (e.g., d,l-bornyl methacrylate),3-tetracyclo[4.4.0.1.1]dodecyl methacrylate, 1-adamantyl methacrylate,isobornyl acrylate, or combinations thereof. In an embodiment, themonofunctional (meth)acrylate monomer comprises isobornyl methacrylate.

In certain embodiments, the weight ratio of the monofunctional(meth)acrylate monomer to the polyurethane (meth)acrylate polymer is60:40 to 40:60, 55:45 to 45:55, or 50:50. Often, the monofunctional(meth)acrylate monomer is present in an amount of 40 parts or more byweight per 100 parts of the total photopolymerizable composition, 45parts or more, 46 parts or more, 47 parts or more, 48 parts or more, 49parts or more, or 50 parts or more; and 65 parts or less, 64 parts orless, 63 parts or less, 62 parts or less, 61 parts or less, 60 parts orless, 59 parts or less, 58 parts or less, 57 parts or less, 56 parts orless, or 55 parts or less, by weight per 100 parts of the totalphotopolymerizable composition.

In some embodiments of the invention, the cured material will be incontact with an aqueous environment. In those cases, it is advantageousto utilize materials which have low affinity for water. The affinity forwater of certain (meth)acrylate monomers can be estimated by thecalculation of a partition coefficient (P) between water and animmiscible solvent, such as octanol. This can serve as a quantitativedescriptor of hydrophilicity or lipophilicity. The octanol/waterpartition coefficient can be calculated by software programs such as ACDChemSketch, (Advanced Chemistry Development, Inc., Toronto, Canada)using the log of octanol/water partition coefficient (log P) module. Inembodiments of the present invention, the calculated log P value isgreater than 1, 1.5, 2, 2.5, 3, 3.5, or 4. The calculated log P value istypically no greater than 12.5. In some embodiments, the calculated logP value is no greater than 12, 11.5, 11, 10.5, 10, 9.5, 9, 8.5, 8, 7.5,7, 6.5, 6, or 5.5. Moreover, in some embodiments, photopolymerizablecompositions exclude the presence of a significant amount of hydrophilic(meth)acrylate monomers by being essentially free of any monofunctional(meth)acrylate monomer having a log P value of less than 3, less than 2,or less than 1.

In some embodiments, photopolymerizable compositions contain hydrophilic(meth)acrylate monomers or polymers (e.g., hydrophilic urethane(meth)acrylate polymer) having a log P value of less than 3, less than2, or less than 1, in an amount of 25% by weight or less, based on thetotal weight of the photopolymerizable composition, such as 23%, 21%,20%, 19%, 17%, 15%, 13%, or 11% or less of hydrophilic components; and1% by weight or more, 2%, 3%, 4%, 5%, 7%, 9%, or 10% or more hydrophiliccomponents, for example 1% to 25% by weight, based on the total weightof the photopolymerizable composition. In some embodiments, thecombination of a hydrophilic component and a monofunctional(meth)acrylate monomer whose cured homopolymer has a T_(g) of 150° C. orgreater can impart advantageous properties to an article, for instance,20% by weight or more, 22%, 25%, 27%, 30%, 32%, 35%, 37%, 40%, 42%, 45%,47%, or 50% by weight or more of a monofunctional (meth)acrylate monomerwhose cured homopolymer has a T_(g) of 150° C. may be included when 1%to 25% by weight of a hydrophilic component is present, each based onthe total weight of the photopolymerizable composition.

TABLE 1 Reported glass transition temperature (T_(g)) and calculated logP (log of octanol/water partition coefficient) of homopolymers ofmonofunctional (meth)acrylate monomers. T_(g) Calculated Monomer (° C.)T_(g) Reference log P 3,3,5-trimethylcyclohexyl 15 Hopfinger et. al.; J.4.38 acrylate Polym. Sci. B., Polym. Phys. 1988, 26, 2007 d,l-isobornylacrylate 94 Jakubowski et. al. 4.22 Polymer, 2008, 49, 1567dicyclopentanyl acrylate 103 U.S. Pat. No. 4,591,626 3.693,5-dimethyl-1-adamantyl 105 Matsumoto, A. et. al. 4.63 acrylateMacromolecules 1991, 24, 4017 cyclohexyl methacrylate 107 Wilson, P.S.,Simha, R.; 3.41 Macromolecules, 1973, 95, 3, 902 tert-butyl methacrylate113 Matsumoto, A. et. al. 2.57 Macromolecules 1991, 24, 40173,3,5-trimethylcyclohexyl 125 Hopfinger et. al.; J. 4.93 methacrylatePolym. Sci. B., Polym. Phys. 1988, 26, 2007 cis-4-tert-butyl-cyclo- 132Matsumoto, A. et. al. 5.13 hexylmethacrylate Macromolecules 1993, 26, 7,1659 2-decahydronapthyl 145 Matsumoto, A. et. al., J. 4.95 methacrylatePolym. Sci. A., Polym. Chem. 1993, 31, 2531 1-adamantyl acrylate 153Matsumoto, A. et. al. 3.68 Macromolecules 1991, 24, 4017 Mixture of 73%163 Matsumoto, A. et. al. 5.13 trans-4-tert-butylcyclohexyl-Macromolecules methacrylate/27% 1993, 26, 7, 1659 cis-4-tert-butyl-cyclohexylmethacrylate dicyclopentanyl methacrylate 173 U.S. Pat. No.4,591,626 4.24 trans-4-tert-butylcyclohexyl 178 Matsumoto, A. et. al.5.13 methacrylate Macromolecules 1993, 26, 7, 1659 d,l-isobornylmethacrylate 191 Matsumoto, A. et. al., 4.77 J. Polym. Sci. A., Polym.Chem. 1993, 31, 2531 3,5-dimethyl-1-adamantyl 194 Matsumoto, A. et. al.5.19 methacrylate Macromolecules 1991, 24, 4017 d,l-bornyl methacrylate194 Matsumoto, A. et. al., 4.77 J. Polym. Sci. A., Polym. Chem. 1993,31, 2531 3-tetracyclo[4.4.0.1.1]dode- 199 Matsumoto, A. et. al., 4.66cyl methacrylate J. Polym. Sci. A., Polym. Chem. 1993, 31, 25311-adamantyl methacrylate >253 Matsumoto, A. et. al. 4.23 Macromolecules1991, 24, 4017 2-ethylhexyl methacrylate −10 Fleischhaker et. al., 4.88Macromol. Chem. Phys. 2014, 215, 1192. tetrahydrofurfuryl 60 E.I. duPont de Nemours 1.38 methacrylate & Co., Ind. Eng. Chem., 1936, 28,1160, 2-phenoxyethyl methacrylate 47 Song et. al.; J. Phys. 3.26 Chem. B2010, 114, 7172 N-vinyl pyrrolidone 180 Turner et. al; Polymer, 0.371985, 26, 757 carboxyethyl acrylate <30 Fang et. al.; Int. J. 0.60Adhes. and Adhes. 84 (2018) 387-393 2-hydroxyethyl methacrylate 105Russell et. al.; J. 0.50 Polym. Sci. Polym. Phys, 1980, 18, 1271acryloyl morpholine 147 Elles, J.; Chimie −0.94 Moderne, 1959, 4, 26, 53

Photoinitiator

Photopolymerizable compositions of the present disclosure include atleast one photoinitiator. Suitable exemplary photoinitiators are thoseavailable under the trade designations OMNIRAD from IGM Resins(Waalwijk, The Netherlands) and include 1-hydroxycyclohexyl phenylketone (OMNIRAD 184), 2,2-dimethoxy-1,2-diphenylethan-1-one (OMNIRAD651), bis(2,4,6 trimethylbenzoyl)phenylphosphineoxide (OMNIRAD 819),1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propane-1-one(OMNIRAD 2959), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone(OMNIRAD 369),2-Dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one(OMNIRAD 379),2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (OMNIRAD907), Oligo[2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone]ESACURE ONE (Lamberti S.p.A., Gallarate, Italy),2-hydroxy-2-methyl-1-phenyl propan-1-one (DAROCUR 1173), 2, 4,6-trimethylbenzoyldiphenylphosphine oxide (OMNIRAD TPO), and 2, 4,6-trimethylbenzoylphenyl phosphinate (OMNIRAD TPO-L). Additionalsuitable photoinitiators include for example and without limitation,benzyl dimethyl ketal, 2-methyl-2-hydroxypropiophenone, benzoin methylether, benzoin isopropyl ether, anisoin methyl ether, aromatic sulfonylchlorides, photoactive oximes, and combinations thereof.

In some embodiments, a photoinitiator is present in a photopolymerizablecomposition in an amount of up to about 5% by weight, based on the totalweight of polymerizable components in the photopolymerizablecomposition. In some cases, a photoinitiator is present in an amount of0.1 wt. % or more, 0.2 wt. % or more, 0.3 wt. % or more, 0.4 wt. % ormore, 0.5 wt. % or more, 0.6 wt. % or more, 0.7 wt. % or more, 0.8 wt. %or more, 0.9 wt. % or more, 1.0 wt. % or more, 1.25 wt. % or more, or1.5 wt. % or more; and 5 wt. % or less, 4.8 wt. % or less, 4.6 wt. % orless, 4.4 wt. % or less, 4.2 wt. % or less, 4.0 wt. % or less, 3.8 wt. %or less, 3.6 wt. % or less, 3.4 wt. % or less, 3.2 wt. % or less, 3.0wt. % or less, 2.8 wt. % or less, 2.6 wt. % or less, 2.4 wt. % or less,2.2 wt. % or less, 2.0 wt. % or less, 1.8 wt. % or less, or 1.6 wt. % orless. Stated another way, the photoinitiator may be present in an amountof about 0.1-5% by weight, 0.2-5% by weight, or 0.5-5% by weight, basedon the total weight of the photopolymerizable composition.

Further, a thermal initiator can optionally be present in aphotopolymerizable composition described herein. In some embodiments, athermal initiator is present in a photopolymerizable composition or inan amount of up to about 5% by weight, based on the total weight ofpolymerizable components in the photopolymerizable composition. In somecases, a thermal initiator is present in an amount of about 0.1-5% byweight, based on the total weight of polymerizable components in thephotopolymerizable composition. Suitable thermal initiators include forinstance and without limitation, peroxides such as benzoyl peroxide,dibenzoyl peroxide, dilauryl peroxide, cyclohexane peroxide, methylethyl ketone peroxide, hydroperoxides, e.g., tert-butyl hydroperoxideand cumene hydroperoxide, dicyclohexyl peroxydicarbonate,2,2,-azo-bis(isobutyronitrile), and t-butyl perbenzoate. Examples ofcommercially available thermal initiators include initiators availablefrom DuPont Specialty Chemical (Wilmington, Del.) under the VAZO tradedesignation including VAZO 67 (2,2′-azo-bis(2-methybutyronitrile)) VAZO64 (2,2′-azo-bis(isobutyronitrile)) and VAZO 52(2,2′-azo-bis(2,2-dimethyvaleronitrile)), and LUCIDOL 70 from ElfAtochem North America, Philadelphia, Pa.

In certain aspects, the use of more than one initiator assists inincreasing the percentage of monomer that gets incorporated into thereaction product of polymerizable components and thus decreasing thepercentage of the monomer that remains uncured.

Components

Orthodontic articles according to the present disclosure comprise apolymerized reaction product of components. The components include atleast one isocyanate, at least one (meth)acrylate mono-ol, at least onepolycarbonate diol, and at least one catalyst. Each of these componentsis discussed in detail below.

Suitable amounts of each of the isocyanate, (meth)acrylate mono-ol, andpolycarbonate diol present in the components are based on molar ratiosof each of these components to the others. For instance, a ratio of theisocyanate (e.g., a diisocyanate, which has 2 isocyanate equivalents permole of isocyanate compound) to the polycarbonate diol typically rangesfrom 4 molar equivalents of the isocyanate to 1 molar equivalent of thealcohol of the polycarbonate diol, to 4 molar equivalents of theisocyanate to 3 molar equivalents of the alcohol of the polycarbonatediol. Stated another way, a ratio of the isocyanate (e.g., adiisocyanate) to the polycarbonate diol typically ranges from 4 molarequivalents of the isocyanate to 1 molar equivalent of the alcohol ofthe polycarbonate diol, to 1.3 molar equivalents of the isocyanate to 1molar equivalent of the alcohol of the polycarbonate diol. In selectembodiments, a ratio of the isocyanate to the polycarbonate diol is 4molar equivalents of isocyanate to 2 molar equivalents of the alcohol ofthe polycarbonate diol, or stated another way, 2 molar equivalents ofisocyanate to 1 molar equivalent of alcohol of the polycarbonate diol.The closer the ratio of the isocyanate to the polycarbonate diol is to 1molar equivalent of isocyanate to 1 molar equivalent of the alcohol ofthe polycarbonate diol, the higher the weight average molecular weightof the resulting polyurethane (meth)acrylate polymer produced in thepolymerization reaction product of components.

A ratio of the isocyanate (e.g., a diisocyanate) to the (meth)acrylatemono-ol typically ranges from 4 molar equivalents of the isocyanate to 3molar equivalents of the (meth)acrylate mono-ol, to 4 molar equivalentsof the isocyanate to 1 molar equivalent of the (meth)acrylate mono-ol.Stated another way, a ratio of the isocyanate (e.g., a diisocyanate) tothe (meth)acrylate mono-ol typically ranges from 1.3 molar equivalentsof the isocyanate to 1 molar equivalent of the (meth)acrylate mono-ol,to 4 molar equivalents of the isocyanate to 1 molar equivalent of the(meth)acrylate mono-ol. In select embodiments, a ratio of the isocyanateto the (meth)acrylate mono-ol is 4 molar equivalents of the isocyanateto 2 molar equivalents of the (meth)acrylate mono-ol, or stated anotherway, 2 molar equivalents of the isocyanate to 1 molar equivalents of the(meth)acrylate mono-ol.

A ratio of the polycarbonate diol to the (meth)acrylate mono-oltypically ranges from 1 molar equivalent of the alcohol of thepolycarbonate diol to 3 molar equivalents of the (meth)acrylate mono-ol,to 3 molar equivalents of the polycarbonate diol to 1 molar equivalentsof the (meth)acrylate mono-ol. Stated another way, a ratio of thepolycarbonate diol to the (meth)acrylate mono-ol typically ranges from 1molar equivalent of the alcohol of the polycarbonate diol to 3 molarequivalents of the (meth)acrylate mono-ol, to 1 molar equivalent of thealcohol of the polycarbonate diol to 0.3 molar equivalents of the(meth)acrylate mono-ol. In select embodiments, a ratio of thepolycarbonate diol to the (meth)acrylate mono-ol is 1 molar equivalentof the alcohol of the polycarbonate diol to 1 molar equivalent of the(meth)acrylate mono-ol.

Isocyanate

The components (e.g., included in the polymerization reaction product ofcomponents) comprise at least one isocyanate. Polyisocyanates which canbe employed in the components can be any organic isocyanate having atleast two free isocyanate groups. Included are aliphatic,cycloaliphatic, aromatic and araliphatic isocyanates. Any of the knownpolyisocyanates such as alkyl and alkylene polyisocyanates, cycloalkyland cycloalkylene polyisocyanates, and combinations such as alkylene andcycloalkylene polyisocyanates can be employed.

In some embodiments, diisocyanates having the formula R_(di)(NCO)₂ canbe used, with R_(di) as defined above.

Specific examples of suitable diisocyanates include for instance andwithout limitation, 2,6-toluene diisocyanate (TDI), 2,4-toluenediisocyanate, methylenedicyclohexylene-4,4′-diisocyanate (H12MDI),3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI),1,6-diisocyanatohexane (HDI), tetramethyl-m-xylylene diisocyanate, amixture of 2,2,4- and 2,4,4-trimethyl-1,6-diisocyanatohexane (TMXDI),trans-1,4-hydrogenated xylylene diisocyanates (H6XDI),cyclohexyl-1,4-diisocyanate, 4,4′-methylene diphenyl diisocyanate,2,4′-methylene diphenyl diisocyanate, a mixture of 4,4′-methylenediphenyl diisocyanate and 2,4′-methylene diphenyl diisocyanate,1,5-naphthalene diisocyanate, 1,4-tetramethylene diisocyanate,1,4-phenylene diisocyanate, 2,6- and 2,4-toluene diisocyanate,1,5-naphthylene diisocyanate, 2,4′ and 4,4′-diphenylmethanediisocyanate, pentamethylene diisocyanate, dodecamethylene diisocyanate,1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, methyl2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate,1,4-bis (isocyanatomethyl) cyclohexane, 1,3-bis (isocyanatomethyl)cyclohexane, 4,4′-toluidine diisocyanate, 4,4′-diphenyl etherdiisocyanate, 1,3- or 1,4-xylylene diisocyanate, lysine diisocyanatemethyl ester, 3,3′-dimethyl-4,4′-diphenylmethane diisocyanate,3,3′-dimethyl-phenylene diisocyanate, 2,5-bis (isocyanatemethyl)-bicyclo[2.2.1]heptane, 2,6-bis (isocyanatemethyl)-bicyclo[2.2.1]heptane, bis (2-isocyanate ethyl) fumarate,4-diphenylpropane diisocyanate,trans-cyclohexane-1,4-diisocyanatehydrogenated dimer acid diisocyanate,a norbornene diisocyanate, methylenebis 6-isopropyl-1,3-phenyldiisocyanate, and any combination thereof. In select embodiments, thediisocyanate comprises IPDI.

It is also possible to use higher-functional polyisocyanates known frompolyurethane chemistry or else modified polyisocyanates, for examplecontaining carbodiimide groups, allophanate groups, isocyanurate groupsand/or biuret groups.

(Meth)acrylate mono-ol

The components (e.g., included in the polymerization reaction product ofcomponents) comprise a (meth)acrylate mono-ol. Typically, the(meth)acrylate mono-ol comprises a hydroxy functional (meth)acrylate ofFormula (II):

HO-Q-(A)_(p)  (II)

wherein Q is a polyvalent organic linking group, A is a (meth)acrylfunctional group of the formula —XC(═O)C(R₃)═CH₂, wherein X is O, S, orNR₄, R₄ is H or alkyl of 1 to 4 carbon atoms, R₃ is a lower alkyl of 1to 4 carbon atoms or H, and wherein p is 1 or 2.

Q can be a straight or branched chain or cycle-containing connectinggroup. Q can include a covalent bond, an alkylene, an arylene, anaralkylene, an alkarylene. Q can optionally include heteroatoms such asO, N, and S, and combinations thereof. Q can also optionally include aheteroatom-containing functional group such as carbonyl or sulfonyl, andcombinations thereof. In some embodiments, Q is a straight chain,branched chain, or cycle-containing connecting group selected fromarylene, aralkylene, and alkarylene. In yet other embodiments, Q is astraight chain, branched chain, or cycle-containing connecting groupcontaining heteroatoms such as O, N, and S and/or a heteroatomcontaining functional group such as carbonyl and sulfonyl. In otherembodiments, Q is a branched or cycle-containing alkylene group thatoptionally contains heteroatoms selected from O, N, S, and/or aheteroatom-containing functional group such as carbonyl and sulfonyl.

In some embodiments, in the hydroxy functional (meth)acrylate of Formula(II), Q is an alkylene group, p is 1, and in the (meth)acryl functionalgroup A, X is O and R₂ is methyl or H. In certain preferred embodiments,in the hydroxy functional (meth)acrylate of Formula (II), Q is analkylene group, p is 1, and in the (meth)acryl functional group A, X isO and R₂ is methyl.

Suitable example (meth)acrylate mono-ols include for instance andwithout limitation, 2-hydroxyethyl (meth)acrylate, hydroxypropylacrylate (all isomers), hydroxybutyl acrylate (all isomers),poly(e-caprolactone) mono[2-(meth) acryloxy ethyl] esters such ascaprolactone monoacrylate available under the trade designation “SR-495”from Sartomer USA (Arkema Group) (Exton, Pa.), glycerol dimethacrylate,1-(acryloxy)-3-(methacryloxy)-2-propanol, 2-hydroxy-3-phenyloxypropyl(meth)acrylate, 2-hydroxyalkyl (meth)acryloyl phosphate,4-hydroxycyclohexyl (meth)acrylate, trimethylolpropane di(meth)acrylate,trimethylolethane di(meth)acrylate, 1,4-butanediol mono(meth)acrylate,neopentyl glycol mono(meth)acrylate, 1,6-hexanediol mono(meth)acrylate,3-chloro-2-hydroxypropyl (meth)acrylate,2-hydroxy-3-alkyloxy(meth)acrylate, polyethylene glycolmono(meth)acrylate, polypropylene glycol mono(meth)acrylate, ethyleneoxide-modified phthalic acid (meth)acrylate, and 4-hydroxycyclohexyl(meth)acrylate.

Polycarbonate diol

The components (e.g., included in the polymerization reaction product ofcomponents) comprise a polycarbonate diol, which was found to contributeto less water being absorbed during contact with water than orthodonticarticles containing polyurethanes having alternate linking groups, suchas polyethers. As orthodontic articles are used in the moisture-richenvironment of a patient's mouth, the extent of water absorption isrelevant to the composition of an orthodontic article. Select articlesabsorb less than 3%, less than 2.5%, less than 2%, less than 1.5%, oreven less than 1% water when soaked in deionized water for 7 days at 37°C. The polycarbonate diol is of Formula (I):

H(O—R₁—O—C(═O))_(m)—O—R₂—OH  (I)

wherein each of R₁ in each (O—R₁—O—C(═O)) repeat unit, and R₂ areindependently an aliphatic, cycloaliphatic, or aliphatic/cycloaliphaticalkylene group and an average number of carbon atoms in a combination ofall the R₁ and R₂ groups is 4 to 10, and m is (an integer of) 2 to 23.Stated another way, while some repeat units of R₁ and/or R₂ may have acarbon number of less than 4 (e.g., 2 or 3), enough of the repeat unitshave a sufficiently high carbon number that when the carbon numbers ofall the repeat units of R₁ and R₂ in the polycarbonate diol of Formula(I) are averaged, that average falls within the range of 4 to 10, or anyof 4 to 6, 4 to 7, 4 to 8, 4 to 9, 5 to 7, 5 to 8, 5 to 9, 5 to 10, 6 to8, 6 to 9, 6 to 10, 7 to 9, 7 to 10, or 8 to 10. In select embodiments,at least one of R₁ or R₂ is —CH₂CH₂CH(CH₃)CH₂CH₂—, —(CH₂)₆—, or—(CH₂)₄—, and preferably a combination of —CH₂CH₂CH(CH₃)CH₂CH₂—, and—(CH₂)₆—.

In some embodiments, either the polycarbonate diol has a number averagemolecular weight (Mn) of greater than 1,000 grams per mole (g/mol) or aweighted average of all polycarbonate diols present in the componentshas a Mn of greater than 1,000 g/mol, wherein Mn is determined by OHvalue. Stated a different way, when the components contain a singlepolycarbonate diol of Formula (I), the polycarbonate diol has a Mnhigher than 1,000 g/mol. When the components contain two or morepolycarbonate diols (e.g., one or more being of Formula (I)), the Mn ofat least one of the polycarbonate diols may be 1,000 g/mol or less withthe proviso that a weighted average of all the Mn values of the two ormore polycarbonate diols is higher than 1,000 g/mol. For instance,components containing two polycarbonate diols could include a molarratio of a first polycarbonate diol having a Mn of about 500 g/mol of 1to a second polycarbonate diol having a Mn of about 1,500 g/mol of 2,resulting in a weighted average Mn of 1,167 g/mol. In certainembodiments, a polycarbonate diol (or a weighted average of all thepolycarbonate diols present in the components) has a number averagemolecular weight of 1,500 g/mol or higher.

In some embodiments, one or more polycarbonate diols are present havinga Mn of 450 grams per mole (g/mol) or greater, 500 g/mol or greater, 550g/mol or greater, 600 g/mol or greater, 650 g/mol or greater, 700 g/molor greater, 750 g/mol or greater, 800 g/mol or greater, 850 g/mol orgreater, 900 g/mol or greater, 950 g/mol or greater, or 1,000 g/mol orgreater; and 3,200 g/mol or less, 3,100 g/mol or less, 3,000 g/mol orless, 2,900 g/mol or less, 2,800 g/mol or less, 2,700 g/mol or less,2,600 g/mol or less, 2,500 g/mol or less, 2,400 g/mol or less, 2,300g/mol or less, 2,200 g/mol or less, 2,100 g/mol or less, 2,000 g/mol orless, 1,900 g/mol or less, 1,800 g/mol or less, or 1,700 g/mol or less.Stated another way, the polycarbonate diol may have a Mn of 450 g/mol to3,200 g/mol, 800 g/mol to 3,200 g/mol, 1,000 g/mol to 3,200 g/mol, 1,500g/mol to 3,200 g/mol, 1,800 g/mol to 3,200 g/mol, 450 g/mol to 2,200g/mol, 800 g/mol to 2,200 g/mol, 1,000 g/mol to 2,200 g/mol, 1,500 g/molto 2,200 g/mol, or 1,800 g/mol to 2,200 g/mol. Inclusion of apolycarbonate diol having a Mn of greater than 3,200 g/mol, on the otherhand, may negatively impact the stiffness of a photopolymerizationreaction product of the photopolymerization composition, by increasingthe elastomeric character of the photopolymerization reaction product.In select embodiments, the photopolymerizable composition is essentiallyfree of any diols that have a Mn lower than the one or morepolycarbonate diols present in the components.

Suitable polycarbonate diols for use in the components include forinstance and without limitation, those commercially available fromKuraray Co. Ltd. (Tokyo, JP) under the trade designation “KURARAYPOLYOL”, e.g., specifically, each of the KURARAY POLYOL C series: C-590,C-1090, C-2050, C-2090, and C-3090; from Covestro LLC (Pittsburgh, Pa.)under the trade designation “DESMOPHEN”, e.g., specifically, each of theDESMOPHEN C series: C-2100, C-2200, and C XP-2613.

Catalyst

The components (e.g., included in the polymerization reaction product ofcomponents) comprise a catalyst to catalyze the reaction of the at leastone isocyanate, at least one (meth)acrylate mono-ol, and at least onepolycarbonate diol. Typically, catalyst is included in an amount of 0.01wt. % to 5 wt. %, based on the total weight of the polymerizablecomponents.

Examples of suitable catalysts include for instance and withoutlimitation, dioctyl dilaurate (DOTDL), stannous octoate, dibutyltindiacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltinthiocarboxylate, dibutyltin dimaleate, dioctyltin mercaptide, dioctyltinthiocarboxylate, lead 2-ethylhexanoate, tetra-alkyl titanates such astetrabutyl titanate (TBT), triethylamine, N, N-dimethylcyclohexylamine,N-methylmorpholine, N-ethylmorpholine, N, N-dimethyl-p-toluidine,beta-(dimethylamino) propionitrile, N-methylpyrrolidone, N,N-dicyclohexylmethylamine, dimethylaminoethanol,dimethylamino-ethoxyethanol, triethylenediamine, N, N, N′-trimethylaminoethyl ethanol amine, N, N, N′, N′-tetramethylethylenediamine, N, N,N′, N′-tetramethyl-1,3-diamine, N, N, N′,N′-tetramethyl-1,6-hexanediol-diamine, bis(N, N-dimethylaminoethyl)ether, N′-cyclohexyl-N, N-dimethyl-formamidine, N,N′-dimethylpiperazine, trimethyl piperazine, bis(aminopropyl)piperazine, N—(N, N′-dimethylaminoethyl) morpholine,bis(morpholinoethyl) ether, 1,2-dimethyl imidazole, N-methylimidazole,1,4-diamidines, diazabicyclo-[2.2.2]-octane (DABCO), 1,4-diazabicyclo[3.3.0]-oct-4-ene (DBN), 1,8-diazabicyclo-[4.3.0]-non-5-ene (DBN),1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU), and phenol salts, salts suchas octyl acid salts, N, N, N′, N″-pentamethyldiethylenetriamine, N, N,N′, N″-pentamethyl dipropylenetriamine, tetramethylguanidine,N-cyclohexyl-N′, N′, N″, N″-tetramethyl guanidine,N-methyl-N′-(2-dimethyl amino ethyl) piperazine, 1,3,5-tris (N,N-dimethyl-propyl)-hexahydro-1,3,5-triazine.

In any embodiment, the catalyst comprises zinc, an amine, tin,zirconium, or bismuth. The catalyst can comprise tin, such as dibutyltindiacrylate. Preferably, however, the catalyst is free of tin, as tincatalysts may not be desirable to include in orthodontic articles thatwill be in contact with a patient's mouth.

The catalyst may comprise an organometallic zinc complex that is free of2-ethylhexyl carboxylate and 2-ethylhexanoic acid, such as the zinccatalyst commercially available from King Industries, Inc. (Norwalk,Conn.) under the trade designation K-KAT XK-672, and/or other zinccatalysts available from King Industries, such as K-KAT XK-661, andK-KAT XK-635. Another suitable catalyst is bismuth neodecanoate, forinstance commercially available from Sigma-Aldrich (St. Louis, Mo.), aswell as bismuth catalysts available from King Industries under the tradedesignations K-KAT XK-651 and K-KAT 348. Available aluminum basedcatalysts include K-KAT 5218 from King Industries. Further, zirconiumbased catalysts include K-KAT 4205 and K-KAT 6212 available from KingIndustries.

Polymerized Reaction Product of Components

Orthodontic articles according to the present disclosure comprise apolymerized reaction product of components, which were described above.The polymerized reaction product of components contains at least onepolyurethane (meth)acrylate polymer. Urethanes are prepared by thereaction of an isocyanate with an alcohol to form carbamate linkages.The polyurethane (meth)acrylate polymer typically provides toughness(e.g., at least a minimum tensile strength and/or modulus andflexibility, (e.g., at least a minimum elongation at break)) to thefinal orthodontic article. In addition to the urethane functionality,the polyurethane (meth)acrylate polymer further comprises apolycarbonate linking group. The linking group is a functional groupthat connects two or more urethane groups, and may be divalent,trivalent, or tetravalent, and preferably divalent. In addition, thepolyurethane (meth)acrylate polymer optionally further comprises one ormore functional groups selected from hydroxyl groups, carboxyl groups,amino groups, and siloxane groups. These functional groups can bereactive with other components of the photopolymerizable compositionduring polymerization. The polyurethane (meth)acrylate polymerpreferably has a weight average molecular weight (Mw) of 3,000 g/mol orgreater, 4,000 g/mol or greater, 5,000 g/mol or greater, 6,000 g/mol orgreater, 6,000 g/mol or greater, 7,000 g/mol or greater, 8,000 g/mol orgreater, 9,000 g/mol or greater, 10,000 g/mol or greater, 11,000 g/molor greater, or 12,000 g/mol or greater; and 50,000 g/mol or less, 45,000g/mol or less, 40,000 g/mol or less, 35,000 g/mol or less, 32,000 g/molor less, 30,000 g/mol or less, 28,000 g/mol or less, 25,000 g/mol orless, 23,000 g/mol or less, 20,000 g/mol or less, or 18,000 g/mol orless. Stated another way, the polyurethane (meth)acrylate polymer mayhave a Mw of 3,000 g/mol to 50,000 g/mol, 6,000 g/mol to 40,000 g/mol,6,000 g/mol to 18,000 g/mol, 6,000 g/mol to 35,000 g/mol, or 8,000 g/molto 32,000 g/mol. Weight average molecular weight may be measured usinggel permeation chromatography (GPC), for instance using the methoddescribed in the Examples below. Higher molecular weight of thepolyurethane (meth)acrylates will result in higher viscosity resinformulations with comparable compositions and loadings, which makes themless flowable; lower molecular weight of the polyurethane(meth)acrylates will reduce their toughening effect on the curedorthodontic articles.

In some embodiments, the polyurethane (meth)acrylate is of Formula (VI):

(A)_(p)-Q-OC(O)NH—R_(di)—NH—C(O)—[O—R_(dOH)—OC(O)NH—R_(dh)—NH—C(O)]_(r)—O-Q-(A)_(p)  (VI)

wherein, A has the formula —OC(═O)C(R₃)═CH₂ wherein R₃ is an alkyl of 1to 4 carbon atoms (e.g. methyl) or H, p is 1 or 2, Q is a polyvalentorganic linking group as described above, Rai is the residue of adiisocyanate, R_(dOH) is the residue of a polycarbonate polyol, and raverages from 1 to 15. In some embodiments, r is no greater than 15, 14,13, 12, 11, or 10. In some embodiments, r averages at least 2, 3, 4, or5. In some embodiments, A is a methacryl functional group, such asmethacrylate.

In some embodiments, the polymerized reaction product of componentsfurther comprises one or more side reaction products in addition to thepolyurethane (meth)acrylate polymer. Depending on the selectivity of thecatalyst and/or the weight ratios of the components, oligomers of thereactants may be produced. The order of addition of components inpreparing the photopolymerizable composition affects the relativeamounts of polymers and oligomers produced in the photopolymerizedreaction product. For instance, adding the isocyanate to thepolycarbonate diol first, followed by adding the monofunctional(meth)acrylate results in a higher ratio of polyurethane (meth)acrylatepolymer to side products such as oligomers, than instead adding themonofunctional (meth)acrylate to the isocyanate first, followed byadding the polycarbonate diol.

Oligomers having a structure of monofunctional (meth)acrylatemonomer-isocyanate-monofunctional (meth)acrylate monomer have been foundto be a byproduct of the polymerization reaction of components incertain embodiments. It is possible to purify the polyurethane(meth)acrylate polymer to remove such side products. Alternatively,additional side products such as oligomers may be added to thepolymerized reaction product, particularly when a specific reactiongenerates a small amount of one or more side products. It has beendiscovered that some side product components can improve at least one ofmodulus or extent of crosslinking after the photopolymerizablecomposition has been cured.

For example, photopolymerizable compositions optionally comprise acompound of Formula (III):

(H₂C═C(R₃)C(═O)—X)_(p)-Q-OC(═O)NH—R_(d)i-NHC(═O)O-Q-(X—C(═O)(R₃)C═CH₂)_(p)  (III)

wherein X, Q, p, and R₃ are as defined for Formula (II), and Rai is theresidue of a diisocyanate as defined above. Typically, the compound ofFormula (III) is produced during the polymerization of the components,as described above. The specific formulation of the components willaffect how much of a compound of Formula (III) is made during thepolymerization of components. For instance, the specificity of thecatalyst towards catalyzing the formation of the polyurethane(meth)acrylate polymer can affect the amount of the compound of Formula(III) generated during the polymerization of the components. In certainembodiments, the compound of Formula (III) is added to thephotopolymerizable composition, particularly when a smaller amount ofthe compound of Formula (III) is produced by the polymerization ofcomponents than desired. In any embodiment, the compound mayadvantageously improve crosslinking during the photopolymerizationreaction, increase the modulus or the photopolymerization reactionproduct, or both. Regardless of if the compound of Formula (III) isformed during the polymerization of the components, added separately tothe photopolymerizable composition, or both, in some embodiments thecompound of Formula (III) is present in an amount of 0.05 weight percent(wt. %) or greater, based on the weight of the polymerizablecomposition, 0.1 wt. % or greater, 0.5 wt. % or greater, 1 wt. % orgreater, 1.5 wt. % or greater, 2.5 wt. % or greater, 2 wt. % or greater,3 wt. % or greater, 4 wt. % or greater, 5 wt. % or greater, 6 wt. % orgreater, 7 wt. % or greater, 8 wt. % or greater, or 9 wt. % or greater;and 20 wt. % or less, 18 wt. % or less, 16 wt. % or less, 15 wt. % orless, 14 wt. % or less, 12 wt. % or less, or 10 wt. % or less, based onthe weight of the polymerizable composition. Stated another way, thecompound of Formula (III) may be present in the photopolymerizablecomposition in an amount of 0.05 to 20 weight percent (wt. %), 1.5 to 12wt. %, 2.5 to 12 wt. %, 5 to 15 wt. %, 5 to 12 wt. %, 7 to 15 wt. %, 7to 12 wt. %, or 5 to 20 wt. %, based on the weight of the polymerizablecomposition. Optionally, X is O in the compound of Formula (III). Inselect embodiments, the compound of Formula (III) is of Formula (IV):

Second Polymerization Reaction Product of Components:

In any embodiment, the photopolymerizable composition further comprisesa second polymerization reaction product of components. The use of asecond polyurethane(meth)acrylate polymer may provide somewhat differentmechanical properties to the orthodontic article than using a singlepolyurethane(meth)acrylate polymer in the photopolymerizablecomposition. The components of the second polymerization reactionproduct comprise:

-   -   1) an isocyanate functional (meth)acrylate compound of the        Formula (VII):

(A)_(p)-Q-NCO  (VII),

-   -   -   wherein A, p, and Q are as defined for Formula (II);

    -   2) a polycarbonate diol of Formula (I):

H(O—R₁—O—C(═O))_(m)O—R₂—OH  (I)

-   -   -   wherein each of R₁ in each (O—R₁—O—C(═O)) repeat unit and            each R₂ are independently an aliphatic, cycloaliphatic, or            aliphatic/cycloaliphatic alkylene group and an average            number of carbon atoms in a combination of all the R₁ and R₂            groups is 4 to 10, and m is 2 to 23; and

    -   3) a catalyst.        The second polymerization reaction product comprises a        polyurethane (meth)acrylate polymer that is different from the        first polyurethane (meth)acrylate polymer. In select        embodiments, the second polymerization reaction product        comprises a compound of Formula (VIII):

(H₂C═C(R₃)C(═O)—O)_(p)-Q-NH—C(═O)—(O—R₁—O—C(═O))_(m)—O—R₂—O—C(═O)NH-Q-(O—C(═O)(R₃)C═CH₂)_(p)  (VIII);

wherein Q, p, and R₃ are as defined for Formula (II) and R₁ and R₂ areas defined for Formula (I).

The compound of Formula (VIII) is typically obtained by reaction of apolycarbonate diol with an isocyanate functional (meth)acrylate compoundin the presence of a catalyst. Examples of the isocyanate functional(meth)acrylate include isocyanatoethyl methacrylate,isocyanatoethoxyethyl methacrylate, isocyanatoethyl acrylate, and1,1-(bisacryloyloxymethyl) ethyl isocyanate, which are for instancecommercially available from Showa Denko (Tokyo, Japan). As an example,the compound of Formula (VIII) may, in select embodiments, be a compoundof Formula (IX):

In Formula (IX), n is about 6.7 for a 1000 molecular weightpolycarbonate diol based on hexane diol.

In some embodiments, the second polymerization reaction productcomprises a compound of Formula (XII):

wherein R_(d), is a residue of a diisocyanate as defined above. Inembodiments in which the diisocyanate is asymmetric, duringpolymerization the orientation of attachment of the residue of thediisocyanate to the nitrogen atoms of the carbamate linkages will varyand the polymerized reaction product will accordingly contain multiplepolyurethane methacrylate structures.

Difunctional Component

The photopolymerizable compositions of the present disclosure optionallyinclude at least one difunctional component, such as a difunctional(meth)acrylate monomer or oligomer. A difunctional component present ina photopolymerizable composition can co-react with the polyurethane(meth)acrylate polymer (e.g., is capable of undergoing additionpolymerization).

A difunctional component (e.g., monomer) is optionally present in anamount of up to 15 wt. %, based on the total weight of thephotopolymerizable composition, up to 12 wt. %, up to 10 wt. %, or up to8 wt. %, based on the total weight of the photopolymerizablecomposition. Including more than 15 wt. % difunctional components maylead to more crosslinking than desired and decrease the elongation ofthe orthodontic article.

Suitable difunctional monomers include for instance and withoutlimitation, compounds having the Formula (X):

H₂C═C(R₃)C(═O)X-Q-O—C(═O)NH—R_(di)—NHC(═O)—O-Q-XC(═O)C(R₃)═CH₂  (X);

wherein R₃ is as defined for Formula (II) and R_(d), is the residue of adiisocyanate, or compounds having the Formula (XI):

H₂C═C(R₃)C(═O)—O-Q-NH—C(═O)—(O—R₁—O—C(═O))_(m)—O—R₂—O—C(═O)NH-Q-O—C(═O)C(R₃)═CH₂  (XI),

wherein Q, X, and R₃ are as defined for Formula (II) and R₁ and R₂ areas defined for Formula (I). Additional suitable difunctional monomersinclude hydroxyethyl methacrylate diester of terephthalic acid,1,12-dodecanediol dimethacrylate, alkoxylated hexanediol diacrylate,alkoxylated neopentyl glycol diacrylate, caprolactone modifiedneopentylglycol hydroxypivalate diacrylate, caprolactone modifiedneopentylglycol hydroxypivalate diacrylate, cyclohexanedimethanoldiacrylate, diethylene glycol diacrylate, dipropylene glycol diacrylate,ethoxylated (10) bisphenol A diacrylate, ethoxylated (3) bisphenol Adiacrylate, ethoxylated (30) bisphenol A diacrylate, ethoxylated (4)bisphenol A diacrylate, hydroxypivalaldehyde modified trimethylolpropanediacrylate, neopentyl glycol diacrylate, polyethylene glycol (200)diacrylate, polyethylene glycol (400) diacrylate, polyethylene glycol(600) diacrylate, propoxylated neopentyl glycol diacrylate,tetraethylene glycol diacrylate, tricyclodecanedimethanol diacrylate,triethylene glycol diacrylate, tripropylene glycol diacrylate, or anycombination thereof. Further suitable difunctional monomers include thedimethacrylates of each of the above listed diacrylates.

Typically, the photopolymerizable compositions are essentially free oftrihydric alcohols, which are alcohols having three hydroxyl groups.This is due to such alcohols increasing the hydrophilicity of thephotopolymerizable composition, which may result in an undesirably highwater absorption during use of an orthodontic article prepared from thephotopolymerizable composition.

Additives

Photopolymerizable compositions described herein, in some instances,further comprise one or more additives, such as one or more additivesselected from the group consisting of inhibitors, stabilizing agents,sensitizers, absorption modifiers, fillers and combinations thereof.

In addition, a photopolymerizable material composition described hereincan further comprise one or more sensitizers to increase theeffectiveness of one or more photoinitiators that may also be present.In some embodiments, a sensitizer comprises isopropylthioxanthone (ITX)or 2-chlorothioxanthone (CTX). Other sensitizers may also be used. Ifused in the photopolymerizable composition, a sensitizer can be presentin an amount ranging of about 0.01% by weight or about 1% by weight,based on the total weight of the photopolymerizable composition.

A photopolymerizable composition described herein optionally alsocomprises one or more polymerization inhibitors or stabilizing agents. Apolymerization inhibitor is often included in a photopolymerizablecomposition to provide additional thermal stability to the composition.A stabilizing agent, in some instances, comprises one or moreanti-oxidants. Any anti-oxidant not inconsistent with the objectives ofthe present disclosure may be used. In some embodiments, for example,suitable anti-oxidants include various aryl compounds, includingbutylated hydroxytoluene (BHT), which can also be used as apolymerization inhibitor in embodiments described herein. In addition toor as an alternative, a polymerization inhibitor comprisesmethoxyhydroquinone (MEHQ).

In some embodiments, a polymerization inhibitor, if used, is present inan amount of about 0.001-2% by weight, 0.001 to 1% by weight, or 0.01-1%by weight, based on the total weight of the photopolymerizablecomposition. Further, if used, a stabilizing agent is present in aphotopolymerizable composition described herein in an amount of about0.1-5% by weight, about 0.5-4% by weight, or about 1-3% by weight, basedon the total weight of the photopolymerizable composition.

A photopolymerizable composition as described herein can also compriseone or more UV absorbers including dyes, optical brighteners, pigments,particulate fillers, etc., to control the penetration depth of actinicradiation. One particularly suitable UV absorber is Tinuvin 326(2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methylphenol,obtained from BASF Corporation, Florham Park, N.J. Another particularlysuitable UV absorber that is an optical brightener that is Tinopal OB, abenzoxazole, 2,2′-(2,5-thiophenediyl)bis[5-(1,1-dimethylethyl)], alsoavailable from BASF Corporation. Another suitable UV absorber is anoptical brightener comprising a compound of Formula (V):

The compound of Formula V may be synthesized as described in detail inthe Examples below.

The UV absorber, if used, can be present in an amount of about 0.001-5%by weight, about 0.01-1% by weight, about 0.1-3% by weight, or about0.1-1% by weight, based on the total weight of the photopolymerizablecomposition.

Photopolymerizable compositions may include fillers, includingnano-scale fillers. Examples of suitable fillers are naturally occurringor synthetic materials including, but not limited to: silica (SiO₂(e.g., quartz)); alumina (Al₂O₃), zirconia, nitrides (e.g., siliconnitride); glasses and fillers derived from, for example, Zr, Sr, Ce, Sb,Sn, Ba, Zn, and Al; feldspar; borosilicate glass; kaolin (china clay);talc; zirconia; titania; and submicron silica particles (e.g., pyrogenicsilicas such as those available under the trade designations AEROSIL,including “OX 50,” “130,” “150” and “200” silicas from Degussa Corp.,Akron, Ohio and CAB-O-SIL M5 and TS-720 silica from Cabot Corp.,Tuscola, Ill.). Organic fillers made from polymeric materials are alsopossible, such as those disclosed in International Publication No.WO09/045752 (Kalgutkar et al.).

The compositions may further contain fibrous reinforcement and colorantssuch as dyes, pigments, and pigment dyes. Examples of suitable fibrousreinforcement include PGA microfibrils, collagen microfibrils, andothers as described in U.S. Pat. No. 6,183,593 (Narang et al.). Examplesof suitable colorants as described in U.S. Pat. No. 5,981,621 (Clark etal.) include 1-hydroxy-4-[4-me thylphenylamino]-9,10-anthracenedione(FD&C violet No. 2); disodium salt of6-hydroxy-5-[(4-sulfophenyl)oxo]-2-naphthalenesulfonic acid (FD&C YellowNo. 6);9-(o-carboxyphenyl)-6-hydroxy-2,4,5,7-tetraiodo-3H-xanthen-3-one,disodium salt, monohydrate (FD&C Red No. 3); and the like.

Discontinuous fibers are also suitable fillers, such as fiberscomprising carbon, ceramic, glass, or combinations thereof. Suitablediscontinuous fibers can have a variety of compositions, such as ceramicfibers. The ceramic fibers can be produced in continuous lengths, whichare chopped or sheared to provide the discontinuous ceramic fibers. Theceramic fibers can be produced from a variety of commercially availableceramic filaments. Examples of filaments useful in forming the ceramicfibers include the ceramic oxide fibers sold under the trademark NEXTEL(3M Company, St. Paul, Minn.). NEXTEL is a continuous filament ceramicoxide fiber having low elongation and shrinkage at operatingtemperatures, and offers good chemical resistance, low thermalconductivity, thermal shock resistance, and low porosity. Specificexamples of NEXTEL fibers include NEXTEL 312, NEXTEL 440, NEXTEL 550,NEXTEL 610 and NEXTEL 720. NEXTEL 312 and NEXTEL 440 are refractoryaluminoborosilicate that includes Al₂O₃, SiO₂ and B₂O₃. NEXTEL 550 andNEXTEL 720 are aluminosilica and NEXTEL 610 is alumina. Duringmanufacture, the NEXTEL filaments are coated with organic sizings orfinishes which serves as aids in textile processing. Sizing can includethe use of starch, oil, wax or other organic ingredients applied to thefilament strand to protect and aid handling. The sizing can be removedfrom the ceramic filaments by heat cleaning the filaments or ceramicfibers as a temperature of 700° C. for one to four hours.

The ceramic fibers can be cut, milled, or chopped so as to providerelatively uniform lengths, which can be accomplished by cuttingcontinuous filaments of the ceramic material in a mechanical shearingoperation or laser cutting operation, among other cutting operations.Given the highly controlled nature of certain cutting operations, thesize distribution of the ceramic fibers is very narrow and allow tocontrol the composite property. The length of the ceramic fiber can bedetermined, for instance, using an optical microscope (Olympus MX61,Tokyo, Japan) fit with a CCD Camera (Olympus DP72, Tokyo, Japan) andanalytic software (Olympus Stream Essentials, Tokyo, Japan). Samples maybe prepared by spreading representative samplings of the ceramic fiberon a glass slide and measuring the lengths of at least 200 ceramicfibers at 10× magnification.

Suitable fibers include for instance ceramic fibers available under thetrade name NEXTEL (available from 3M Company, St. Paul, Minn.), such asNEXTEL 312, 440, 610 and 720. One presently preferred ceramic fibercomprises polycrystalline α-Al₂O₃. Suitable alumina fibers aredescribed, for example, in U.S. Pat. No. 4,954,462 (Wood et al.) andU.S. Pat. No. 5,185,299 (Wood et al.). Exemplary alpha alumina fibersare marketed under the trade designation NEXTEL 610 (3M Company, St.Paul, Minn.). In some embodiments, the alumina fibers arepolycrystalline alpha alumina fibers and comprise, on a theoreticaloxide basis, greater than 99 percent by weight Al₂O₃ and 0.2-0.5 percentby weight SiO₂, based on the total weight of the alumina fibers. Inother embodiments, some desirable polycrystalline, alpha alumina fiberscomprise alpha alumina having an average grain size of less than onemicrometer (or even, in some embodiments, less than 0.5 micrometer). Insome embodiments, polycrystalline, alpha alumina fibers have an averagetensile strength of at least 1.6 GPa (in some embodiments, at least 2.1GPa, or even, at least 2.8 GPa). Suitable aluminosilicate fibers aredescribed, for example, in U.S. Pat. No. 4,047,965 (Karst et al).Exemplary aluminosilicate fibers are marketed under the tradedesignations NEXTEL 440, and NEXTEL 720, by 3M Company (St. Paul,Minn.). Aluminoborosilicate fibers are described, for example, in U.S.Pat. No. 3,795,524 (Sowman). Exemplary aluminoborosilicate fibers aremarketed under the trade designation NEXTEL 312 by 3M Company. Boronnitride fibers can be made, for example, as described in U.S. Pat. No.3,429,722 (Economy) and U.S. Pat. No. 5,780,154 (Okano et al.).

Ceramic fibers can also be formed from other suitable ceramic oxidefilaments. Examples of such ceramic oxide filaments include thoseavailable from Central Glass Fiber Co., Ltd. (e.g., EFH75-01,EFH150-31). Also preferred are aluminoborosilicate glass fibers, whichcontain less than about 2% alkali or are substantially free of alkali(i.e., “E-glass” fibers). E-glass fibers are available from numerouscommercial suppliers.

Examples of useful pigments include, without limitation: white pigments,such as titanium oxide, zinc phosphate, zinc sulfide, zinc oxide andlithopone; red and red-orange pigments, such as iron oxide (maroon, red,light red), iron/chrome oxide, cadmium sulfoselenide and cadmium mercury(maroon, red, orange); ultramarine (blue, pink and violet), chrome-tin(pink) manganese (violet), cobalt (violet); orange, yellow and buffpigments such as barium titanate, cadmium sulfide (yellow), chrome(orange, yellow), molybdate (orange), zinc chromate (yellow), nickeltitanate (yellow), iron oxide (yellow), nickel tungsten titanium, zincferrite and chrome titanate; brown pigments such as iron oxide (buff,brown), manganese/antimony/titanium oxide, manganese titanate, naturalsiennas (umbers), titanium tungsten manganese; blue-green pigments, suchas chrome aluminate (blue), chrome cobalt-alumina (turquoise), iron blue(blue), manganese (blue), chrome and chrome oxide (green) and titaniumgreen; as well as black pigments, such as iron oxide black and carbonblack. Combinations of pigments are generally used to achieve thedesired color tone in the cured composition.

The use of florescent dyes and pigments can also be beneficial inenabling the printed composition to be viewed under black-light. Aparticularly useful hydrocarbon soluble fluorescing dye is2,5-bis(5-tert-butyl-2-benzoxazolyl) 1 thiophene. Fluorescing dyes, suchas rhodamine, may also be bound to cationic polymers and incorporated aspart of the resin.

If desired, the compositions of the disclosure may contain otheradditives such as indicators, accelerators, surfactants, wetting agents,antioxidants, tartaric acid, chelating agents, buffering agents, andother similar ingredients that will be apparent to those skilled in theart. Additionally, medicaments or other therapeutic substances can beoptionally added to the photopolymerizable compositions. Examplesinclude, but are not limited to, fluoride sources, whitening agents,anticaries agents (e.g., xylitol), remineralizing agents (e.g., calciumphosphate compounds and other calcium sources and phosphate sources),enzymes, breath fresheners, anesthetics, clotting agents, acidneutralizers, chemotherapeutic agents, immune response modifiers,thixotropes, polyols, anti-inflammatory agents, antimicrobial agents,antifungal agents, agents for treating xerostomia, desensitizers, andthe like, of the type often used in dental compositions.

Combinations of any of the above additives may also be employed. Theselection and amount of any one such additive can be selected by one ofskill in the art to accomplish the desired result without undueexperimentation.

Photopolymerizable compositions materials herein can also exhibit avariety of desirable properties, non-cured, cured, and as post-curedarticles. A photopolymerizable composition, when non-cured, has aviscosity profile consistent with the requirements and parameters of oneor more additive manufacturing devices (e.g., 3D printing systems).Advantageously, in many embodiments the photopolymerizable compositioncontains a minimal amount of solvent. For instance, the composition maycomprise 95% to 100% solids, preferably 100% solids. In some instances,a photopolymerizable composition described herein when non-curedexhibits a dynamic viscosity of about 0.1-1,000 Pa·s, about 0.1-100Pa·s, or about 1-10 Pa·s using a TA Instruments AR-G2 magnetic bearingrheometer using a 40 mm cone and plate measuring system at 40 degreesCelsius and at a shear rate of 0.11/s. In some cases, aphotopolymerizable composition described herein when non-cured exhibitsa dynamic viscosity of less than about 10 Pa·s.

Orthodontic Articles

A polymerized reaction product of a photopolymerizable compositionaccording to the above disclosure comprises a shape of an orthodonticarticle. The conformability and durability of a cured orthodonticarticle made from the photopolymerizable compositions of the presentdisclosure can be determined in part by standard tensile, modulus,and/or elongation testing. The photopolymerizable compositions cantypically be characterized by at least one of the following parametersafter hardening.

The orthodontic article preferably exhibits at least one desirablephysical property. These physical properties include the following:initial relaxation modulus, elongation at break, tensile strength,relaxation modulus at 30 minutes, percent loss of relaxation modulus,weight percent extractable components, and exhibiting peaks in lossmodulus and tan delta with large temperature separation, and percentweight of water absorption. Preferably, the orthodontic article exhibitsat least two different desirable physical properties, more preferably atleast three different desirable physical properties, and most preferablyat least initial relaxation modulus, elongation at break, and tensilestrength. The values of these different physical properties aredescribed below.

An orthodontic article optionally exhibits an initial relaxation modulusof 100 megapascals (MPa) or greater measured at 37° C. and 2% strain, asdetermined by Dynamic Mechanical Analysis (DMA) following conditioning(i.e., soaking) of a sample of the material of the orthodontic articlein deionized water for 48 hours at room temperature (i.e., 22 to 25° C.)(“Water Conditioning”). The DMA procedure is described in detail in theExamples below. Preferably, an orthodontic article exhibits an initialrelaxation modulus of 200 MPa or greater, 300 MPa or greater, 400 MPa orgreater, 500 MPa or greater, 600 MPa or greater, 700 MPa or greater, 800MPa or greater, 900 MPa or greater, 1,000 MPa or greater, 1,100 MPa orgreater, or even 1,200 MPa or greater. In some embodiments, the initialrelaxation modulus is no greater than about 3000, 2500, 2000, or 1500MPa.

An orthodontic article optionally exhibits a (e.g., 30 minute)relaxation modulus of 100 MPa or greater as determined by DMA following30 minutes of soaking in water at 37° C. under a 2% strain. The DMAprocedure for relaxation modulus is described in detail in the Examplesbelow, and is performed on a sample of the material of the orthodonticarticle following Water Conditioning and initial relaxation modulustesting. Preferably, an orthodontic article exhibits a (e.g., 30 minute)relaxation modulus of 200 MPa or greater, 300 MPa or greater, 400 MPa orgreater, 500 MPa or greater, 600 MPa or greater, 700 MPa or greater, 800MPa or greater, 900 MPa or greater, or even 1,000 MPa or greater. Insome embodiments, the (e.g., 30 minute) relaxation modulus is no greaterthan about 1500, 1200, 1000, or 800 MPa.

An orthodontic article optionally exhibits a percent loss of relaxationmodulus of 70% or less as determined by DMA. The loss is determined bycomparing the initial relaxation modulus to the (e.g., 30 minute)relaxation modulus at 37° C. and 2% strain. It was discovered thatorthodontic articles according to at least certain embodiments of thepresent disclosure exhibit a smaller loss in relaxation modulusfollowing exposure to water than articles made of different materials.Preferably, an orthodontic article exhibits loss of relaxation modulusof 65% or less, 60% or less, 55% or less, 50% or less, 45% or less 40%or less, or even 35% or less. In some embodiments, the loss ofrelaxation modulus is 10%, 15%, or 20% or greater.

An orthodontic article optionally exhibits an elongation at break of aprinted article of 20% or greater, as determined according to theExamples section below, after conditioning (i.e., soaking) of a sampleof the material of the orthodontic article in phosphate-buffered salinehaving a pH of 7.4, for 24 hours at a temperature of 37° C. (“PBSConditioning”). High elongation at break helps prevent the orthodonticarticle from being too brittle and potentially breaking during use by apatient. Preferably, an orthodontic article exhibits an elongation atbreak of 25% or greater, 30% or greater, 35% or greater, 40% or greater,45% or greater, 50% or greater, 55% or greater, 60% or greater, 65% orgreater, 70% or greater, 75% or greater, 80% or greater, 85% or greater,90% or greater, 95% or greater, 100% or greater, 110% or greater, oreven 120% or greater. In some embodiments, the elongation at break is nogreater than 250%, 240%, 230%, 220%, 210%, 200%, 190%, 180%, 170%, 160%,150%, or 140%.

An orthodontic article optionally exhibits a tensile strength at yield(or maximum) of 14 MPa or greater as determined according toASTM-D638-14, using test specimen V, after PBS Conditioning. Strength atyield (i.e., yield strength) is defined as the maximum tensile stress amaterial can handle before it is permanently deformed. Tensile strengthat break refers to the point on the stress-strain curve where thematerial breaks. As used herein, samples that yield have a distinct peakin the stress-strain curve. The stress-strain curves for brittlematerials, however, do not have a yield point and are often linear overthe full range of strain, eventually terminating in fracture at amaximum tensile strength without appreciable plastic flow. High tensilestrength contributes to the orthodontic article having sufficientstrength to be resilient during use in a patient's mouth. Preferably, anorthodontic article exhibits a tensile strength of 15 MPa or greater, 17MPa or greater, 20 MPa or greater, 25 MPa or greater, 30 MPa or greater,35 MPa or greater, 40 MPa or greater, 45 MPa or greater, 50 MPa orgreater, or even 55 MPa or greater. In some embodiments, the tensilestrength is no greater than 100 MPa, 95 MPa, 90 MPa, 85 MPa, 80 MPa, 75MPa, or 70 MPa.

In select embodiments, an orthodontic article exhibits an initialrelaxation modulus of 100 MPa, an elongation at break of 20% or greater,and a tensile strength of 14 MPa or greater. Similarly, an article mayexhibit any combination of the preferred values described above, of eachof the initial relaxation modulus, elongation at break, and tensilestrength at yield. It was unexpectedly found that photopolymerizablecompositions according to at least certain embodiments are capable offorming articles simultaneously having all three of these physicalproperties.

In select embodiments, dynamic mechanical analysis of articles showed aspecific type of response that gave high elongation with high relaxationmodulus at 30 minutes. When measured at a frequency of 1 Hz and atemperature heating ramp rate of 2° C./min from below −40° C. to above200° C., some embodiments according to the present disclosure display apeak in the loss modulus below 20° C., more preferably below 15° C.,most preferably below 10° C. In some embodiments, the peak loss modulustemperature is at least −70° C., −60° C., or −50° C. The term peak doesnot necessarily mean the global maximum value in loss modulus, but canbe a local maximum value, or a shoulder on a larger peak. These articlestend to display high levels of elongation at break. In otherembodiments, articles may display a tan delta peak >60° C., >80° C.,more preferably >100° C., most preferably >110° C. In some embodiments,the peak tan delta temperature is no greater than 150° C., 140° C., 135°C., or 130° C. Articles which displayed high 30 minute relaxationmodulus displayed tan delta peaks >60° C. Articles which displayed bothhigh elongation and high 30 minute relaxation modulus displayed a peakin the loss modulus below 20° C. and a tan delta peak greater than 60°C. Loss modulus and tan delta are explained, for instance, in Sepe, M.P. (1998 Dynamic Mechanical Analysis for Plastics Engineering. WilliamAndrew Publishing/Plastics Design Library).

In at least certain embodiments of orthodontic articles of the presentdisclosure, the articles are advantageously more resistant to stainingthan articles made from different, more hydrophilic components. Forinstance, dyes and other colored materials in beverages are typicallyhydrophilic, thus they will have a greater affinity for a morehydrophilic composition than a more hydrophobic composition.

In certain embodiments, an orthodontic article comprises 2 wt. % or lessextractable components, 1 wt. % or less, 0.75 wt. % or less, 0.5 wt. %or less, or even 0.1% or less extractable components, based on the totalweight of the article. Either an organic solvent or water can be used toextract component, as described in detail in the Examples below.Post-processing of the orthodontic article to assist in achieving a lowextractable component-containing article is discussed in more detailbelow.

The above mechanical properties are particularly well suited fororthodontic articles that require resiliency and flexibility, along withadequate wear strength and low hygroscopicity.

Methods

In a second aspect, the present disclosure provides a method of makingan orthodontic article. The method comprises:

-   -   a) obtaining a photopolymerizable composition comprising:        -   i) a monofunctional (meth)acrylate monomer whose cured            homopolymer has a T_(g) of 90° C. or greater;        -   ii) a photoinitiator;            -   and        -   iii) a polymerization reaction product of components, the            components comprising:            -   1) an isocyanate;            -   2) a (meth)acrylate mono-ol;            -   3) a polycarbonate diol of Formula (I):

H(O—R₁—O—C(═O))_(m)O—R₂—OH  (I)

-   -   -   -   -   wherein each of R₁ in each (O—R₁—O—C(═O)) repeat                    unit and each R₂ are independently an aliphatic,                    cycloaliphatic, or                -   aliphatic/cycloaliphatic alkylene group and an                    average number of carbon atoms in a combination of                    all the R₁ and R₂ groups is 4 to 10, and m is 2 to                    23; and

            -   4) a catalyst;

    -   b) selectively curing the photopolymerizable composition; and

    -   c) repeating steps a) and b) to form multiple layers and create        the orthodontic article.

Photopolymerizable compositions described herein can be mixed by knowntechniques. In some embodiments, for instance, a method for thepreparation of a photopolymerizable composition described hereincomprises the steps of mixing all or substantially all of the componentsof the photopolymerizable composition, heating the mixture, andoptionally filtering the heated mixture. Softening the mixture, in someembodiments, is carried out at a temperature of about 50° C. or in arange from about 50° C. to about 85° C. In some embodiments, aphotopolymerizable composition described herein is produced by placingall or substantially all components of the composition in a reactionvessel and heating the resulting mixture to a temperature ranging fromabout 50° C. to about 85° C. with stirring. The heating and stirring arecontinued until the mixture attains a substantially homogenized state.

In many embodiments, the photopolymerizable composition is vatpolymerized, as discussed in detail below.

The shape of the article is not limited, and typically comprises ashaped integral article, in which more than one variation in dimensionis provided by a single integral article. For example, the article cancomprise one or more channels, one or more undercuts, one or moreperforations, or combinations thereof. Such features are typically notpossible to provide in an integral article using conventional moldingmethods. Specific orthodontic articles are described in further detailbelow.

The components of the photopolymerizable composition are as discussed indetail above. In many embodiments, the photopolymerizable composition iscured using actinic radiation comprising UV radiation, e-beam radiation,visible radiation, or a combination thereof. Moreover, the methodoptionally further comprises post curing the orthodontic article usingactinic radiation.

In certain embodiments, the method comprises vat polymerization of thephotopolymerizable composition. When vat polymerization is employed, theradiation may be directed through a wall of a container (e.g., a vat)holding the photopolymerizable composition, such as a side wall or abottom wall.

A photopolymerizable composition described herein in a cured state, insome embodiments, can exhibit one or more desired properties. Aphotopolymerizable composition in a “cured” state can comprise aphotopolymerizable composition that includes a polymerizable componentthat has been at least partially polymerized and/or crosslinked. Forinstance, in some instances, a cured article is at least about 10%polymerized or crosslinked or at least about 30% polymerized orcrosslinked. In some cases, a cured photopolymerizable composition is atleast about 50%, at least about 70%, at least about 80%, or at leastabout 90% polymerized or crosslinked. A cured photopolymerizablecomposition can also be between about 10% and about 99% polymerized orcrosslinked.

Fabricating an Orthodontic Article

Once prepared as set forth above, the photopolymerizable compositions ofthe present disclosure may be used in myriad additive manufacturingprocesses to create a variety of e.g., orthodontic articles. Ageneralized method 100 for creating three-dimensional articles isillustrated in FIG. 1. Each step in the method will be discussed ingreater detail below. First, in Step 110 the desired photopolymerizablecomposition (e.g., comprising at least one polyurethane (meth)acrylatepolymer) is provided and introduced into a reservoir, cartridge, orother suitable container for use by or in an additive manufacturingdevice. The additive manufacturing device selectively cures thephotopolymerizable composition according to a set of computerized designinstructions in Step 120. In Step 130, Step 110 and/or Step 120 isrepeated to form multiple layers to create the article comprising athree-dimensional structure (i.e., an orthodontic article). Optionallyuncured photopolymerizable composition is removed from the article inStep 140, further optionally, the article is subjected to additionalcuring to polymerize remaining uncured photopolymerizable components inthe article in Step 150, and yet further optionally, the article issubjected to a heat treatment in Step 160.

Methods of printing a three-dimensional article or object describedherein can include forming the article from a plurality of layers of aphotopolymerizable composition described herein in a layer-by-layermanner. Further, the layers of a build material composition can bedeposited according to an image of the three-dimensional article in acomputer readable format. In some or all embodiments, thephotopolymerizable composition is deposited according to preselectedcomputer aided design (CAD) parameters.

Additionally, it is to be understood that methods of manufacturing a 3Darticle described herein can include so-called “stereolithography/vatpolymerization” 3D printing methods. Other techniques forthree-dimensional manufacturing are known, and may be suitably adaptedto use in the applications described herein. More generally,three-dimensional fabrication techniques continue to become available.All such techniques may be adapted to use with photopolymerizablecompositions described herein, provided they offer compatiblefabrication viscosities and resolutions for the specified articleproperties. Fabrication may be performed using any of the fabricationtechnologies described herein, either alone or in various combinations,using data representing a three-dimensional object, which may bereformatted or otherwise adapted as necessary for a particular printingor other fabrication technology.

It is entirely possible to form a 3D article from a photopolymerizablecomposition described herein using vat polymerization (e.g.,stereolithography). For example, in some cases, a method of printing a3D article comprises retaining a photopolymerizable compositiondescribed herein in a fluid state in a container and selectivelyapplying energy to the photopolymerizable composition in the containerto solidify at least a portion of a fluid layer of thephotopolymerizable composition, thereby forming a hardened layer thatdefines a cross-section of the 3D article. Additionally, a methoddescribed herein can further comprise raising or lowering the hardenedlayer of photopolymerizable composition to provide a new or second fluidlayer of unhardened photopolymerizable composition at the surface of thefluid in the container, followed by again selectively applying energy tothe photopolymerizable composition in the container to solidify at leasta portion of the new or second fluid layer of the photopolymerizablecomposition to form a second solidified layer that defines a secondcross-section of the 3D article. Further, the first and secondcross-sections of the 3D article can be bonded or adhered to one anotherin the z-direction (or build direction corresponding to the direction ofraising or lowering recited above) by the application of the energy forsolidifying the photopolymerizable composition. Moreover, selectivelyapplying energy to the photopolymerizable composition in the containercan comprise applying actinic radiation, such as UV radiation, visibleradiation, or e-beam radiation, having a sufficient energy to cure thephotopolymerizable composition. A method described herein can alsocomprise planarizing a new layer of fluid photopolymerizable compositionprovided by raising or lowering an elevator platform. Such planarizationcan be carried out, in some cases, by utilizing a wiper or roller or arecoater. Planarization corrects the thickness of one or more layersprior to curing the material by evening the dispensed material to removeexcess material and create a uniformly smooth exposed or flat up-facingsurface on the support platform of the printer.

It is further to be understood that the foregoing process can berepeated a selected number of times to provide the 3D article. Forexample, in some cases, this process can be repeated “n” number oftimes. Further, it is to be understood that one or more steps of amethod described herein, such as a step of selectively applying energyto a layer of photopolymerizable composition, can be carried outaccording to an image of the 3D article in a computer-readable format.Suitable stereolithography printers include the Viper Pro SLA, availablefrom 3D Systems, Rock Hill, S.C. and the Asiga PICO PLUS 39, availablefrom Asiga USA, Anaheim Hills, Calif.

FIG. 2 shows an exemplary stereolithography apparatus (“SLA”) that maybe used with the photopolymerizable compositions and methods describedherein. In general, the SLA 200 may include a laser 202, optics 204, asteering lens 206, an elevator 208, a platform 210, and a straight edge212, within a vat 214 filled with the photopolymerizable composition. Inoperation, the laser 202 is steered across a surface of thephotopolymerizable composition to cure a cross-section of thephotopolymerizable composition, after which the elevator 208 slightlylowers the platform 210 and another cross section is cured. The straightedge 212 may sweep the surface of the cured composition between layersto smooth and normalize the surface prior to addition of a new layer. Inother embodiments, the vat 214 may be slowly filled with liquid resinwhile an article is drawn, layer by layer, onto the top surface of thephotopolymerizable composition.

A related technology, vat polymerization with Digital Light Processing(“DLP”), also employs a container of curable polymer (e.g.,photopolymerizable composition). However, in a DLP based system, atwo-dimensional cross section is projected onto the curable material tocure the desired section of an entire plane transverse to the projectedbeam at one time. All such curable polymer systems as may be adapted touse with the photopolymerizable compositions described herein areintended to fall within the scope of the term “vat polymerizationsystem” as used herein. In certain embodiments, an apparatus adapted tobe used in a continuous mode may be employed, such as an apparatuscommercially available from Carbon 3D, Inc. (Redwood City, Calif.), forinstance as described in U.S. Pat. Nos. 9,205,601 and 9,360,757 (both toDeSimone et al.).

Referring to FIG. 5, a general schematic is provided of another SLAapparatus that may be used with photopolymerizable compositions andmethods described herein. In general, the apparatus 500 may include alaser 502, optics 504, a steering lens 506, an elevator 508, and aplatform 510, within a vat 514 filled with the photopolymerizablecomposition 519. In operation, the laser 502 is steered through a wall520 (e.g., the floor) of the vat 514 and into the photopolymerizablecomposition to cure a cross-section of the photopolymerizablecomposition 519 to form an article 517, after which the elevator 508slightly raises the platform 510 and another cross section is cured.

More generally, the photopolymerizable composition is typically curedusing actinic radiation, such as UV radiation, e-beam radiation, visibleradiation, or any combination thereof. The skilled practitioner canselect a suitable radiation source and range of wavelengths for aparticular application without undue experimentation.

After the 3D article has been formed, it is typically removed from theadditive manufacturing apparatus and rinsed, (e.g., an ultrasonic, orbubbling, or spray rinse in a solvent, which would dissolve a portion ofthe uncured photopolymerizable composition but not the cured, solidstate article (e.g., green body). Any other conventional method forcleaning the article and removing uncured material at the articlesurface may also be utilized. At this stage, the three-dimensionalarticle typically has sufficient green strength for handling in theremaining optional steps of method 100.

It is expected in certain embodiments of the present disclosure that theformed article obtained in Step 120 will shrink (i.e., reduce in volume)such that the dimensions of the article after (optional) Step 150 willbe smaller than expected. For example, a cured article may shrink lessthan 5% in volume, less than 4%, less than 3%, less than 2%, or evenless than 1% in volume, which is contrast to other compositions thatprovide articles that shrink about 6-8% in volume upon optional postcuring. The amount of volume percent shrinkage will not typically resultin a significant distortion in the shape of the final object. It isparticularly contemplated, therefore, that dimensions in the digitalrepresentation of the eventual cured article may be scaled according toa global scale factor to compensate for this shrinkage. For example, insome embodiments, at least a portion of the digital articlerepresentation can be at least 101% of the desired size of the printedappliance, in some embodiments at least 102%, in some embodiments atleast 104%, in some embodiments, at least 105%, and in some embodiments,at least 110%.

A global scale factor may be calculated for any given photopolymerizablecomposition formulation by creating a calibration part according toSteps 110 and 120 above. The dimensions of the calibration article canbe measured prior to post curing.

In general, the three-dimensional article formed by initial additivemanufacturing in Step 120, as discussed above, is not fully cured, bywhich is meant that not all of the photopolymerizable material in thecomposition has polymerized even after rinsing. Some uncuredphotopolymerizable material is typically removed from the surface of theprinted article during a cleaning process (e.g., optional Step 140). Thearticle surface, as well as the bulk article itself, typically stillretains uncured photopolymerizable material, suggesting further cure.Removing residual uncured photopolymerizable composition is particularlyuseful when the article is going to subsequently be post cured, tominimize uncured residual photopolymerizable composition fromundesirably curing directly onto the article.

Further curing can be accomplished by further irradiating with actinicradiation, heating, or both. Exposure to actinic radiation can beaccomplished with any convenient radiation source, generally UVradiation, visible radiation, and/or e-beam radiation, for a timeranging from about 10 to over 60 minutes. Heating is generally carriedout at a temperature in the range of about 75-150° C., for a timeranging from about 10 to over 60 minutes in an inert atmosphere. Socalled post cure ovens, which combine UV radiation and thermal energy,are particularly well suited for use in the post cure processes of Step150 and/or Step 160. In general, post curing improves the mechanicalproperties and stability of the three-dimensional article relative tothe same three-dimensional article that is not post cured.

One particularly attractive opportunity for 3D printing is in the directcreation of orthodontic clear tray aligners. These trays, also known asaligners or polymeric or shell appliances, are provided in a series andare intended to be worn in succession, over a period of months, in orderto gradually move the teeth in incremental steps towards a desiredtarget arrangement. Some types of clear tray aligners have a row oftooth-shaped receptacles for receiving each tooth of the patient'sdental arch, and the receptacles are oriented in slightly differentpositions from one appliance to the next in order to incrementally urgeeach tooth toward its desired target position by virtue of the resilientproperties of the polymeric material. A variety of methods have beenproposed in the past for manufacturing clear tray aligners and otherresilient appliances. Typically, positive dental arch models arefabricated for each dental arch using additive manufacturing methodssuch as stereolithography described above. Subsequently, a sheet ofpolymeric material is placed over each of the arch models and formedunder heat, pressure and/or vacuum to conform to the model teeth of eachmodel arch. The formed sheet is cleaned and trimmed as needed and theresulting arch-shaped appliance is shipped along with the desired numberof other appliances to the treating professional.

An aligner or other resilient appliance created directly by 3D printingwould eliminate the need to print a mold of the dental arch and furtherthermoform the appliance. It also would allow new aligner designs andgive more degrees of freedom in the treatment plan. Exemplary methods ofdirect printing clear tray aligners and other resilient orthodonticapparatuses are set forth in PCT Publication Nos. WO2016/109660 (Raby etal.), WO2016/148960 (Cinader et al.), and WO2016/149007 (Oda et al.) aswell as US Publication Nos. US2011/0091832 (Kim, et al.) andUS2013/0095446 (Kitching).

The following describes general methods for creating a clear trayaligner as printed appliance 300. However, other dental and orthodonticarticles can be created using similar techniques and thephotopolymerizable compositions of the present disclosure.Representative examples include, but are not limited to, the removableappliances having occlusal windows described in InternationalApplication Publication No. WO2016/109660 (Raby et al.), the removableappliances with a palatal plate described in US Publication No.2014/0356799 (Cinader et al); and the resilient polymeric arch membersdescribed in International Application Nos. WO2016/148960 andWO2016/149007 (Oda et al.); as well as US Publication No. 2008/0248442(Cinader et al.). Moreover, the photopolymerizable compositions can beused in the creation of indirect bonding trays, such as those describedin International Publication No. WO2015/094842 (Paehl et al.) and USPublication No. 2011/0091832 (Kim, et al.) and other dental articles,including but not limited to crowns, bridges, veneers, inlays, onlays,fillings, and prostheses (e.g., partial or full dentures). Otherorthodontic appliances and devices include, but not limited to,orthodontic brackets, buccal tubes, lingual retainers, orthodonticbands, class II and class III correctors, sleep apnea devices, biteopeners, buttons, cleats, and other attachment devices.

Fabricating an Orthodontic Appliance with the PhotopolymerizableCompositions

One particularly interesting implementation of an article is generallydepicted in FIG. 3. The additive manufactured article 300 is a cleartray aligner and is removably positionable over some or all of apatient's teeth. In some embodiments, the appliance 300 is one of aplurality of incremental adjustment appliances. The appliance 300 maycomprise a shell having an inner cavity. The inner cavity is shaped toreceive and resiliently reposition teeth from one tooth arrangement to asuccessive tooth arrangement. The inner cavity may include a pluralityof receptacles, each of which is adapted to connect to and receive arespective tooth of the patient's dental arch. The receptacles arespaced apart from each other along the length of the cavity, althoughadjoining regions of adjacent receptacles can be in communication witheach other. In some embodiments, the shell fits over all teeth presentin the upper jaw or lower jaw. Typically, only certain one(s) of theteeth will be repositioned while others of the teeth will provide a baseor anchor region for holding the dental appliance in place as it appliesthe resilient repositioning force against the tooth or teeth to betreated.

In order to facilitate positioning of the teeth of the patient, at leastone of the receptacles may be aligned to apply rotational and/ortranslational forces to the corresponding tooth of the patient when theappliance 300 is worn by the patient in order to eventually align saidtooth to a new desired position. In some particular examples, theappliance 300 may be configured to provide only compressive or linearforces. In the same or different examples, the appliance 300 may beconfigured to apply translational forces to one or more of the teethwithin receptacles.

In some embodiments, the shell of the appliance 300 fits over some orall anterior teeth present in an upper jaw or lower jaw. Typically, onlycertain one(s) of the teeth will be repositioned while others of theteeth will provide a base or anchor region for holding the appliance inplace as it applies the resilient repositioning force against the toothor teeth to be repositioned. An appliance 300 can accordingly bedesigned such that any receptacle is shaped to facilitate retention ofthe tooth in a particular position in order to maintain the currentposition of the tooth.

A method 400 of creating an orthodontic appliance using thephotopolymerizable compositions of the present disclosure can includegeneral steps as outlined in FIG. 4. Individual aspects of the processare discussed in further detail below. The process includes generating atreatment plan for repositioning a patient's teeth. Briefly, a treatmentplan can include obtaining data representing an initial arrangement ofthe patient's teeth (Step 410), which typically includes obtaining animpression or scan of the patient's teeth prior to the onset oftreatment. The treatment plan will also include identifying a final ortarget arrangement of the patient's anterior and posterior teeth asdesired (Step 420), as well as a plurality of planned successive orintermediary tooth arrangements for moving at least the anterior teethalong a treatment path from the initial arrangement toward the selectedfinal or target arrangement (Step 430). One or more appliances can bevirtually designed based on the treatment plan (Step 440), and imagedata representing the appliance designs can exported in STL format, orin any other suitable computer processable format, to an additivemanufacturing device (e.g., a 3D printer system) (Step 450). Anappliance can be manufactured using a photopolymerizable composition ofthe present disclosure retained in the additive manufacturing device(Step 460).

In some embodiments, a (e.g., non-transitory) machine-readable medium isemployed in additive manufacturing of articles according to at leastcertain aspects of the present disclosure. Data is typically stored onthe machine-readable medium. The data represents a three-dimensionalmodel of an article, which can be accessed by at least one computerprocessor interfacing with additive manufacturing equipment (e.g., a 3Dprinter, a manufacturing device, etc.). The data is used to cause theadditive manufacturing equipment to create an article comprising areaction product of a photopolymerizable composition, thephotopolymerizable composition includes a blend of: i) a monofunctional(meth)acrylate monomer whose cured homopolymer has a T_(g) of 90° C. orgreater; ii) a photoinitiator; and iii) a polymerization reactionproduct of components. The components include 1) an isocyanate; 2) a(meth)acrylate mono-ol; a polycarbonate diol of Formula (I):H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 3) a catalyst. Each of R₁ in each(O—R₁—O—C(═O)) repeat unit and each R₂ are independently an aliphatic,cycloaliphatic, or aliphatic/cycloaliphatic alkylene group and anaverage number of carbon atoms in a combination of all the R₁ and R₂groups is 4 to 10, and m is (an integer of) 2 to 23. The polymerizedreaction product of the photopolymerizable composition has a shape ofthe orthodontic article. The details of the photopolymerizablecomposition are as described above.

Data representing an article may be generated using computer modelingsuch as computer aided design (CAD) data. Image data representing the(e.g., polymeric) article design can be exported in STL format, or inany other suitable computer processable format, to the additivemanufacturing equipment. Scanning methods to scan a three-dimensionalobject may also be employed to create the data representing the article.One exemplary technique for acquiring the data is digital scanning Anyother suitable scanning technique may be used for scanning an article,including X-ray radiography, laser scanning, computed tomography (CT),magnetic resonance imaging (MRI), and ultrasound imaging. Other possiblescanning methods are described, e.g., in U.S. Patent ApplicationPublication No. 2007/0031791 (Cinader, Jr., et al.). The initial digitaldata set, which may include both raw data from scanning operations anddata representing articles derived from the raw data, can be processedto segment an article design from any surrounding structures (e.g., asupport for the article). In select embodiments, scanning techniques mayinclude, for example, scanning a patient's mouth to customize anorthodontic article for the patient.

Often, machine-readable media are provided as part of a computingdevice. The computing device may have one or more processors, volatilememory (RAM), a device for reading machine-readable media, andinput/output devices, such as a display, a keyboard, and a pointingdevice. Further, a computing device may also include other software,firmware, or combinations thereof, such as an operating system and otherapplication software. A computing device may be, for example, aworkstation, a laptop, a personal digital assistant (PDA), a server, amainframe or any other general-purpose or application-specific computingdevice. A computing device may read executable software instructionsfrom a computer-readable medium (such as a hard drive, a CD-ROM, or acomputer memory), or may receive instructions from another sourcelogically connected to computer, such as another networked computer.Referring to FIG. 10, a computing device 1000 often includes an internalprocessor 1080, a display 1100 (e.g., a monitor), and one or more inputdevices such as a keyboard 1140 and a mouse 1120. In FIG. 10, an alignerarticle 1130 is shown on the display 1100.

Referring to FIG. 6, in certain embodiments, the present disclosureprovides a system 600. The system 600 comprises a display 620 thatdisplays a 3D model 610 of an article (e.g., an aligner 1130 as shown onthe display 1100 of FIG. 10); and one or more processors 630 that, inresponse to the 3D model 610 selected by a user, cause a 3Dprinter/additive manufacturing device 650 to create a physical object ofthe article 660. Often, an input device 640 (e.g., keyboard and/ormouse) is employed with the display 620 and the at least one processor630, particularly for the user to select the 3D model 610. The article660 comprises a reaction product of a photopolymerizable composition,the photopolymerizable composition includes a blend of: i) amonofunctional (meth)acrylate monomer whose cured homopolymer has aT_(g) of 90° C. or greater; ii) a photoinitiator; and iii) apolymerization reaction product of components. The components include 1)an isocyanate; 2) a (meth)acrylate mono-ol; a polycarbonate diol ofFormula (I): H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 3) a catalyst. Each ofR₁ in each (O—R₁—O—C(═O)) repeat unit and each R₂ are independently analiphatic, cycloaliphatic, or aliphatic/cycloaliphatic alkylene groupand an average number of carbon atoms in a combination of all the R₁ andR₂ groups is 4 to 10, and m is 2 to 23. The polymerized reaction productof the photopolymerizable composition has a shape of the orthodonticarticle. The details of the photopolymerizable composition are asdescribed above.

Referring to FIG. 7, a processor 720 (or more than one processor) is incommunication with each of a machine-readable medium 710 (e.g., anon-transitory medium), a 3D printer/additive manufacturing device 740,and optionally a display 730 for viewing by a user. The 3Dprinter/additive manufacturing device 740 is configured to make one ormore articles 750 based on instructions from the processor 720 providingdata representing a 3D model of the article 750 (e.g., an alignerarticle 1130 as shown on the display 1100 of FIG. 10) from themachine-readable medium 710.

Referring to FIG. 8, for example and without limitation, an additivemanufacturing method comprises retrieving 810, from a (e.g.,non-transitory) machine-readable medium, data representing a 3D model ofan article according to at least one embodiment of the presentdisclosure. The method further includes executing 820, by one or moreprocessors, an additive manufacturing application interfacing with amanufacturing device using the data; and generating 830, by themanufacturing device, a physical object of the article. The additivemanufacturing equipment can selectively cure a photopolymerizablecomposition to form an article. The article comprises a reaction productof a photopolymerizable composition, the photopolymerizable compositionincludes a blend of: i) a monofunctional (meth)acrylate monomer whosecured homopolymer has a T_(g) of 90° C. or greater; ii) aphotoinitiator; and iii) a polymerization reaction product ofcomponents. The components include 1) an isocyanate; 2) a (meth)acrylatemono-ol; a polycarbonate diol of Formula (I):H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 3) a catalyst. Each of R₁ in each(O—R₁—O—C(═O)) repeat unit and each R₂ are independently an aliphatic,cycloaliphatic, or aliphatic/cycloaliphatic alkylene group and anaverage number of carbon atoms in a combination of all the R₁ and R₂groups is 4 to 10, and m is 2 to 23. The polymerized reaction product ofthe photopolymerizable composition has a shape of the orthodonticarticle. The details of the photopolymerizable composition are asdescribed above. One or more various optional post-processing steps 840may be undertaken. Typically, remaining unpolymerized photopolymerizablecomponent may be cured. The article comprises an orthodontic article.

Additionally, referring to FIG. 9, a method of making an articlecomprises receiving 910, by a manufacturing device having one or moreprocessors, a digital object comprising data specifying a plurality oflayers of an article; and generating 920, with the manufacturing deviceby an additive manufacturing process, the article based on the digitalobject. Again, the article may undergo one or more steps ofpost-processing 930.

Select Embodiments of the Disclosure

Embodiment 1 is an orthodontic article. The orthodontic article includesa reaction product of a photopolymerizable composition. Thephotopolymerizable composition includes a) a polymerized reactionproduct of a photopolymerizable composition. The photopolymerizablecomposition includes i) a monofunctional (meth)acrylate monomer whosecured homopolymer has a T_(g) of 90° C. or greater; ii) aphotoinitiator; and iii) a polymerization reaction product ofcomponents. The components include 1) an isocyanate; 2) a (meth)acrylatemono-ol; 3) a polycarbonate diol of Formula (I):H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 4) a catalyst. Each of R₁ in each(O—R₁—O—C(═O)) repeat unit and each R₂ are independently an aliphatic,cycloaliphatic, or aliphatic/cycloaliphatic alkylene group and anaverage number of carbon atoms in a combination of all the R₁ and R₂groups is 4 to 10, and m is 2 to 23. The polymerized reaction product ofthe photopolymerizable composition has a shape of the orthodonticarticle.

Embodiment 2 is the orthodontic article of embodiment 1, wherein the(meth)acrylate mono-ol is of Formula (II): HO-Q-(A) (II). Q is apolyvalent organic linking group, A is a (meth)acryl functional group ofthe formula —XC(═O)C(R₃)═CH₂, wherein X is O, S, or NR₄, R₄ is H oralkyl of 1 to 4 carbon atoms, R₃ is a lower alkyl of 1 to 4 carbon atomsor H, and wherein p is 1 or 2.

Embodiment 3 is the orthodontic article of embodiment 2, wherein in thehydroxy functional (meth)acrylate of Formula (II), Q is an alkylenegroup, p is 1, and in the (meth)acryl functional group A, X is O and R₃is methyl or H.

Embodiment 4 is the orthodontic article of embodiment 2 or embodiment 3,wherein in the hydroxy functional (meth)acrylate of Formula (II), Q isan alkylene group, p is 1, and in the (meth)acryl functional group A, Xis O and R₃ is methyl.

Embodiment 5 is the orthodontic article of any of embodiments 1 to 4,wherein the photopolymerizable composition further includes a compoundof Formula (III):

(H₂C═C(R₃)C(═O)—X)_(p)-Q-OC(═O)NH—R_(di)—NHC(═O)O-Q-(X—C(═O)(R₃)C═CH₂)_(p)  (III).

X, Q, p, and R₃ are as defined for Formula (II), and R_(d), is theresidue of a diisocyanate.

Embodiment 6 is the orthodontic article of embodiment 5, wherein thecompound of Formula (III) is produced during the polymerization of thecomponents.

Embodiment 7 is the orthodontic article of embodiment 5 or embodiment 6,wherein the compound of Formula (III) is added to the photopolymerizablecomposition.

Embodiment 8 is the orthodontic article of any of embodiments 5 to 7,wherein the compound of Formula (III) is present in an amount of 0.05 to20 weight percent (wt. %), based on the weight of the polymerizablecomposition.

Embodiment 9 is the orthodontic article of any of embodiments 5 to 8,wherein the compound of Formula (III) is present in an amount of 1.5 to12 wt. %, based on the weight of the polymerizable composition.

Embodiment 10 is the orthodontic article of any of embodiments 5 to 8,wherein the compound of Formula (III) is present in an amount of 5 to 20wt. %, based on the weight of the polymerizable composition.

Embodiment 11 is the orthodontic article of any of embodiments 5 to 10,wherein X is O in the compound of Formula (III).

Embodiment 12 is the orthodontic article of any of embodiments 5 to 11,wherein the compound of Formula (III) is of Formula (IV):

Embodiment 13 is the orthodontic article of any of embodiments 1 to 12,wherein the photopolymerizable composition further includes adifunctional (meth)acrylate monomer or oligomer.

Embodiment 14 is the orthodontic article of any of embodiments 1 to 13,wherein the monofunctional (meth)acrylate monomer is selected from thegroup consisting of dicyclopentadienyl acrylate, dicyclopentanylacrylate, isobornyl acrylate, dimethyl-1-adamantyl acrylate, cyclohexylmethacrylate, butyl methacrylate (e.g., tert-butyl methacrylate),3,3,5-trimethylcyclohexyl methacrylate, butyl-cyclohexylmethacrylate(e.g., cis-4-tert-butyl-cyclohexylmethacrylate, 73/27trans/cis-4-tert-butylcyclohexylmethacrylate, and/ortrans-4-tert-butylcyclohexyl methacrylate) 2-decahydronapthylmethacrylate, 1-adamantyl acrylate, dicyclopentadienyl methacrylate,isobornyl methacrylate (e.g., d,l-isobornyl methacrylate),dimethyl-1-adamantyl methacrylate, bornyl methacrylate (e.g., d,l-bornylmethacrylate), 3-tetracyclo[4.4.0.1.1]dodecyl methacrylate, 1-adamantylmethacrylate, or combinations thereof.

Embodiment 15 is the orthodontic article of any of embodiments 1 to 14,wherein a weight ratio of the monofunctional (meth)acrylate monomer tothe polyurethane (meth)acrylate polymer is 60:40 to 40:60.

Embodiment 16 is the orthodontic article of any of embodiments 1 to 15,wherein a weight ratio of the monofunctional (meth)acrylate monomer tothe polyurethane (meth)acrylate polymer is 55:45 to 45:55.

Embodiment 17 is the orthodontic article of any of embodiments 1 to 16,wherein the isocyanate includes a diisocyanate selected from the groupconsisting of 2,6-toluene diisocyanate (TDI),methylenedicyclohexylene-4,4′-diisocyanate (H12MDI),3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI),1,6-diisocyanatohexane (HDI), tetramethyl-m-xylylene diisocyanate, amixture of 2,2,4- and 2,4,4-trimethyl-1,6-diisocyanatohexame (TMXDI),trans-1,4-hydrogenated xylylene diisocyanates (H₆XDI), or combinationsthereof.

Embodiment 18 is the orthodontic article of any of embodiments 1 to 17,wherein the isocyanate includes IPDI.

Embodiment 19 is the orthodontic article of any of embodiments 1 to 18,wherein the polycarbonate diol has a molecular weight of 450 grams permole (g/mol) to 3,200 g/mol, or 1,800 g/mol to 3,200 g/mol.

Embodiment 20 is the orthodontic article of any of embodiments 1 to 19,wherein the polycarbonate diol has a molecular weight of 800 g/mol to2,200 g/mol or 1,800 g/mol to 2,200 g/mol

Embodiment 21 is the orthodontic article of any of embodiments 1 to 20,wherein the photopolymerizable composition has a solids content of 95%to 100% solids.

Embodiment 22 is the orthodontic article of any of embodiments 1 to 21,wherein the photopolymerizable composition has a solids content of 100%solids.

Embodiment 23 is the orthodontic article of any of embodiments 1 to 22,wherein the photopolymerizable composition further includes a UVabsorber comprising an optical brightener in an amount of 0.001 to 5% byweight, based on the total weight of the photopolymerizable composition.

Embodiment 24 is the orthodontic article of embodiment 23, wherein theoptical brightener includes a compound of Formula (V):

Embodiment 25 is the orthodontic article of any of embodiments 1 to 24,wherein the photopolymerizable composition further includes an inhibitorin an amount of 0.001 to 1 wt. %, based on the total weight of thephotopolymerizable composition.

Embodiment 26 is the orthodontic article of any of embodiments 1 to 25,wherein the photoinitiator is present in an amount of 0.2 to 5 wt. %,based on the total weight of the photopolymerizable composition.

Embodiment 27 is the orthodontic article of any of embodiments 1 to 26,wherein the catalyst contains zinc.

Embodiment 28 is the orthodontic article of any of embodiments 1 to 27,wherein the catalyst includes an organometallic zinc complex and is freeof 2-ethylhexyl carboxylate and 2-ethylhexanoic acid.

Embodiment 29 is the orthodontic article of any of embodiments 1 to 28,wherein the catalyst is free of tin.

Embodiment 30 is the orthodontic article of any of embodiments 1 to 29,wherein the catalyst contains bismuth.

Embodiment 31 is the orthodontic article of any of embodiments 1 to 30,wherein the polyurethane (meth)acrylate polymer has a weight averagemolecular weight (Mw) of 6,000 g/mol to 35,000 g/mol.

Embodiment 32 is the orthodontic article of any of embodiments 1 to 31,wherein the photopolymerizable composition further includes adifunctional monomer in an amount of up to 15 wt. %, based on the totalweight of the photopolymerizable composition.

Embodiment 33 is the orthodontic article of embodiment 32, wherein thedifunctional monomer includes a compound of Formula (X):H₂C═C(R₃)C(═O)X-Q-O—C(═O)NH—R_(dh)—NHC(═O)—O-Q-XC(═O)C(R₃)═CH₂ (X),wherein R_(dt) is the residue of a diisocyanate, Q, X, and R₃ are asdefined for Formula (II).

Embodiment 34 is the orthodontic article of embodiment 32, wherein thedifunctional monomer includes a compound of Formula (XI):H₂C═C(R₃)C(═O)—O-Q-NH—C(═O)—(O—R₁—O—C(═O))_(m)—O—R₂—O—C(═O)NH-Q-O—C(═O)C(R₃)═CH₂(XI) wherein Q and R₃ are as defined for Formula (II) and R₁ and R₂ areas defined for Formula (I).

Embodiment 35 is the orthodontic article of any of embodiments 1 to 34,wherein a ratio of the isocyanate to the polycarbonate diol ranges from4 molar equivalents of the isocyanate to 1 molar equivalent of thealcohol of the polycarbonate diol, to 4 molar equivalents of theisocyanate to 3 molar equivalents of the alcohol of the polycarbonatediol.

Embodiment 36 is the orthodontic article of embodiment 35, wherein theratio of the isocyanate to the alcohol of the polycarbonate diol is 4molar equivalents of isocyanate to 2 molar equivalents of the alcohol ofthe polycarbonate diol.

Embodiment 37 is the orthodontic article of any of embodiments 1 to 36,wherein a ratio of the isocyanate to the (meth)acrylate mono-ol rangesfrom 4 molar equivalents of the isocyanate to 3 molar equivalents of the(meth)acrylate mono-ol to 4 molar equivalents of the isocyanate to 1molar equivalent of the (meth)acrylate mono-ol.

Embodiment 38 is the orthodontic article of any of embodiments 1 to 37,wherein a ratio of the isocyanate to the (meth)acrylate mono-ol is 4molar equivalents of the isocyanate to 2 molar equivalents of the(meth)acrylate mono-ol.

Embodiment 39 is the orthodontic article of any of embodiments 1 to 38,wherein a ratio of the polycarbonate diol to the (meth)acrylate mono-olranges from 1 molar equivalent of the alcohol of the polycarbonate diolto 3 molar equivalents of the (meth)acrylate mono-ol, to 3 molarequivalents of the alcohol of the polycarbonate diol to 1 molarequivalents of the (meth)acrylate mono-ol.

Embodiment 40 is the orthodontic article of any of embodiments 1 to 39,wherein a ratio of the polycarbonate diol to the (meth)acrylate mono-olis 1 molar equivalent of the alcohol of the polycarbonate diol to 1molar equivalent of the (meth)acrylate mono-ol.

Embodiment 41 is the orthodontic article of any of embodiments 1 to 40,wherein the polyurethane (meth)acrylate is of Formula (VI):

(A)_(p)-Q-OC(O)NH—R_(d)—NH—C(O)—[O—R_(dOH)—OC(O)NH—R_(dh)—NH—C(O)]_(r)—O-Q-(A)_(p)  (VI)

wherein, A has the formula —OC(═O)C(R₃)═CH₂, wherein R₃ is an alkyl of 1to 4 carbon atoms (e.g. methyl) or H, p is 1 or 2, Q is a polyvalentorganic linking group as described above, Rai is the residue of adiisocyanate, R_(dOH) is the residue of a polycarbonate polyol, and raverages from 1 to 15.

Embodiment 42 is the orthodontic article of any of claims 1 to 41,wherein the photopolymerizable composition further includes a secondpolymerization reaction product of components. The components include 1)an isocyanate functional (meth)acrylate compound of Formula (VII):(A)_(p)-Q-NCO (VII), wherein A, p, and Q are as defined for Formula(II); 2) a polycarbonate diol of Formula (I): H(O—R₁—O—C(═O))_(m)O—R₂—OH(I); and 3) a catalyst. Each of R₁ in each (O—R₁—O—C(═O)) repeat unitand each R₂ are independently an aliphatic, cycloaliphatic, oraliphatic/cycloaliphatic alkylene group and an average number of carbonatoms in a combination of all the R₁ and R₂ groups is 4 to 10, and m is2 to 23.

Embodiment 43 is the orthodontic article of any of embodiments 1 to 42,wherein the second polymerization reaction product includes a compoundof Formula (VIII):

(H₂C═C(R₃)C(═O)—O)_(p)-Q-NH—C(═O)—(O—R₁—O—C(═O))_(m)O—R₂—O—C(═O)NH-Q-(O—C(═O)(R₃)C═CH₂)_(p)  (VIII).

Q, p, and R₃ are as defined for Formula (II) and R₁ and R₂ are asdefined for Formula (I).

Embodiment 44 is the orthodontic article of embodiment 43, wherein thecompound of Formula (VIII) is a compound of Formula (IX):

wherein n is about 6.7 for a 1000 molecular weight polycarbonate diolbased on hexane diol

Embodiment 45 is the orthodontic article of any of embodiments 1 to 44,wherein a cured homopolymer of the monofunctional (meth)acrylate monomerhas a T_(g) of 100° C. or greater.

Embodiment 46 is the orthodontic article of any of embodiments 1 to 45,wherein the cured homopolymer of the monofunctional (meth)acrylatemonomer has a T_(g) of 170° C. or greater or 180° C. or greater.

Embodiment 47 is the orthodontic article of any of embodiments 1 to 46,wherein the monofunctional acrylate monomer includes a cycloaliphaticmonofunctional (meth)acrylate.

Embodiment 48 is the orthodontic article of any of embodiments 1 to 47,wherein the monofunctional acrylate monomer includes isobornylmethacrylate.

Embodiment 49 is the orthodontic article of any of embodiments 1 to 48,exhibiting an initial relaxation modulus of 100 megapascals (MPa) orgreater measured at 2% strain at 37° C.

Embodiment 50 is the orthodontic article of any of embodiments 1 to 49,exhibiting a percent loss of relaxation modulus of 70% or less.

Embodiment 51 is the orthodontic article of any of embodiments 1 to 50,exhibiting a percent loss of relaxation modulus of 40% or less.

Embodiment 52 is the orthodontic article of any of embodiments 1 to 51,exhibiting a relaxation modulus of 100 MPa or greater.

Embodiment 53 is the orthodontic article of any of embodiments 1 to 52,exhibiting an elongation at break of a printed article of 20% orgreater.

Embodiment 54 is the orthodontic article of any of embodiments 1 to 53,exhibiting an elongation at break of a printed article of 70% orgreater.

Embodiment 55 is the orthodontic article of any of embodiments 1 to 54,exhibiting a tensile strength at yield of 14 MPa or greater.

Embodiment 56 is the orthodontic article of any of embodiments 1 to 55,exhibiting a tensile strength at yield of 25 MPa or greater

Embodiment 57 is the orthodontic article of any of embodiments 1 to 56,including 1 wt. % or less extractable components.

Embodiment 58 is the orthodontic article of any of embodiments 1 to 57,exhibiting a peak in loss modulus of 20° C. or less.

Embodiment 59 is the orthodontic article of embodiment 58, exhibiting atan delta peak of 80° C. or greater.

Embodiment 60 is the orthodontic article of any of embodiments 1 to 57,wherein the orthodontic article includes a dental tray, a retainer, oran aligner.

Embodiment 61 is the orthodontic article of any of embodiments 1 to 58,wherein the orthodontic article includes an aligner.

Embodiment 62 is a method of making an orthodontic article. The methodincludes a) obtaining a photopolymerizable composition; b) selectivelycuring the photopolymerizable composition; and c) repeating steps a) andb) to form multiple layers and create the orthodontic article. Thephotopolymerizable composition includes i) a monofunctional(meth)acrylate monomer whose cured homopolymer has a T_(g) of 90° C. orgreater; ii) a photoinitiator; and iii) a polymerization reactionproduct of components. The components include 1) an isocyanate; 2) a(meth)acrylate mono-ol; 3) a polycarbonate diol of Formula (I):H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 4) a catalyst. Each of R₁ in each(O—R₁—O—C(═O)) repeat unit and each R₂ are independently an aliphatic,cycloaliphatic, or aliphatic/cycloaliphatic alkylene group and anaverage number of carbon atoms in a combination of all the groups R₁ andR₂ is 4 to 10, and m is 2 to 23.

Embodiment 63 is the method of embodiment 62, wherein thephotopolymerizable composition is cured using actinic radiationincluding UV radiation, e-beam radiation, visible radiation, or acombination thereof.

Embodiment 64 is the method of embodiment 63, wherein the actinicradiation is directed through a wall of a container holding thephotopolymerizable composition.

Embodiment 65 is the method of embodiment 63 or embodiment 64, wherein90% or greater of the actinic radiation is absorbed over a distance of150 micrometers of the photopolymerizable composition.

Embodiment 66 is the method of any of embodiments 62 to 65, wherein thephotopolymerizable composition is cured through a floor of a containerholding the photopolymerizable composition.

Embodiment 67 is the method of any of embodiments 62 to 66, furtherincluding post curing the orthodontic article using actinic radiation.

Embodiment 68 is the method of any of embodiments 62 to 67, wherein themethod includes vat polymerization of the photopolymerizablecomposition.

Embodiment 69 is the method of any of embodiments 62 to 68, furtherincluding subjecting the orthodontic article to a heat treatment.

Embodiment 70 is the method of any of embodiments 62 to 69, wherein thephotopolymerizable composition further includes at least one filler.

Embodiment 71 is the method of any of embodiments 62 to 70, wherein thephotopolymerizable composition further includes at least one fillerselected from silica, alumina, zirconia, and discontinuous fibers.

Embodiment 72 is the method of embodiment 71, wherein the discontinuousfibers include carbon, ceramic, glass, or combinations thereof.

Embodiment 73 is the method of any of embodiments 62 to 72, wherein the(meth)acrylate mono-ol is of Formula (II): HO-Q-(A)_(p) (II). Q is apolyvalent organic linking group, A is a (meth)acryl functional group ofthe formula —XC(═O)C(R₃)═CH₂, wherein X is O, S, or NR₄, R₄ is H oralkyl of 1 to 4 carbon atoms, R₃ is a lower alkyl of 1 to 4 carbon atomsor H, and wherein p is 1 or 2.

Embodiment 74 is the method of embodiment 73, wherein in the hydroxyfunctional (meth)acrylate of Formula (II), Q is an alkylene group, p is1, and in the (meth)acryl functional group A, X is O and R₃ is methyl orH.

Embodiment 75 is the method of embodiment 73 or embodiment 74, whereinin the hydroxy functional (meth)acrylate of Formula (II), Q is analkylene group, p is 1, and in the (meth)acryl functional group A, X isO and R₃ is methyl.

Embodiment 76 is the method of any of claims 62 to 75, wherein thephotopolymerizable composition further includes a compound of Formula(III):

(H₂C═C(R₃)C(═O)—X)_(p)-Q-OC(═O)NH—R_(di)—NHC(═O)O-Q-(X—C(═O)(R₃)C═CH₂)_(p)  (III).

X, Q, p, and R₃ are as defined for Formula (II), and R_(d), is theresidue of a diisocyanate.

Embodiment 77 is the method of embodiment 76, wherein the compound ofFormula (III) is produced during the polymerization of the components.

Embodiment 78 is the method of embodiment 76 or embodiment 77, whereinthe compound of Formula (III) is added to the photopolymerizablecomposition.

Embodiment 79 is the method of any of claims 76 to 78, wherein thecompound of Formula (III) is present in an amount of 0.05 to 20 weightpercent (wt. %), based on the weight of the polymerizable composition.

Embodiment 80 is the method of any of embodiments 76 to 79, wherein thecompound of Formula (III) is present in an amount of 1.5 to 12 wt. %,based on the weight of the polymerizable composition.

Embodiment 81 is the method of any of embodiments 76 to 79, wherein thecompound of Formula (III) is present in an amount of 5 to 20 wt. %,based on the weight of the polymerizable composition.

Embodiment 82 is the method of any of embodiments 76 to 81, wherein X isO in the compound of Formula (III).

Embodiment 83 is the method of any of embodiments 76 to 82, wherein thecompound of Formula (III) is of Formula (IV):

Embodiment 84 is the method of any of embodiments 62 to 83, wherein thephotopolymerizable composition further includes a difunctional(meth)acrylate monomer or oligomer.

Embodiment 85 is the method of any of embodiments 62 to 84, wherein themonofunctional (meth)acrylate monomer is selected from the groupconsisting of dicyclopentadienyl acrylate, dicyclopentanyl acrylate,isobornyl acrylate, dimethyl-1-adamantyl acrylate, cyclohexylmethacrylate, butyl methacrylate (e.g., tert-butyl methacrylate),3,3,5-trimethylcyclohexyl methacrylate, butyl-cyclohexylmethacrylate(e.g., cis-4-tert-butyl-cyclohexylmethacrylate, 73/27trans/cis-4-tert-butylcyclohexylmethacrylate, and/ortrans-4-tert-butylcyclohexyl methacrylate) 2-decahydronapthylmethacrylate, 1-adamantyl acrylate, dicyclopentadienyl methacrylate,isobornyl methacrylate (e.g., d,l-isobornyl methacrylate),dimethyl-1-adamantyl methacrylate, bornyl methacrylate (e.g., d,l-bornylmethacrylate), 3-tetracyclo[4.4.0.1.1]dodecyl methacrylate, 1-adamantylmethacrylate, or combinations thereof.

Embodiment 86 is the method of any of embodiments 62 to 85, wherein aweight ratio of the monofunctional (meth)acrylate monomer to thepolyurethane (meth)acrylate polymer is 60:40 to 40:60.

Embodiment 87 is the method of any of embodiments 62 to 86, wherein aweight ratio of the monofunctional (meth)acrylate monomer to thepolyurethane (meth)acrylate polymer is 55:45 to 45:55.

Embodiment 88 is the method of any of embodiments 62 to 87, wherein theisocyanate includes a diisocyanate selected from the group consisting of2,6-toluene diisocyanate (TDI),methylenedicyclohexylene-4,4′-diisocyanate (H12MDI),3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI),1,6-diisocyanatohexane (HDI), tetramethyl-m-xylylene diisocyanate, amixture of 2,2,4- and 2,4,4-trimethyl-1,6-diisocyanatohexame (TMXDI),trans-1,4-hydrogenated xylylene diisocyanates (H6XDI), or combinationsthereof.

Embodiment 89 is the method of any of embodiments 62 to 88, wherein theisocyanate comprises IPDI.

Embodiment 90 is the method of any of embodiments 62 to 89, wherein thepolycarbonate diol has a molecular weight of 450 grams per mole (g/mol)to 3,200 g/mol, or 1,800 g/mol to 3,200 g/mol.

Embodiment 91 is the method of any of embodiments 62 to 91, wherein thepolycarbonate diol has a molecular weight of 800 g/mol to 2,200 g/mol,or 1,800 g/mol to 2,200 g/mol.

Embodiment 92 is the method of any of embodiments 62 to 91, wherein thephotopolymerizable composition has a solids content of 95% to 100%solids.

Embodiment 93 is the method of any of embodiments 62 to 92, wherein thephotopolymerizable composition has a solids content of 100% solids.

Embodiment 94 is the method of any of embodiments 62 to 93, wherein thephotopolymerizable composition further comprises a UV absorbercomprising an optical brightener in an amount of 0.001 to 5% by weight,based on the total weight of the photopolymerizable composition.

Embodiment 95 is the method of embodiment 94, wherein the opticalbrightener includes a compound of Formula (V):

Embodiment 96 is the method of any of embodiments 62 to 95, wherein thephotopolymerizable composition further includes an inhibitor in anamount of 0.001 to 1 wt. %, based on the total weight of thephotopolymerizable composition.

Embodiment 97 is the method of any of embodiments 62 to 96, wherein thephotoinitiator is present in an amount of 0.2 to 5 wt. %, based on thetotal weight of the photopolymerizable composition.

Embodiment 98 is the method of any of embodiments 62 to 97, wherein thecatalyst contains zinc.

Embodiment 99 is the method of any of embodiments 62 to 98, wherein thecatalyst includes an organometallic zinc complex and is free of2-ethylhexyl carboxylate and 2-ethylhexanoic acid.

Embodiment 100 is the method of any of embodiments 62 to 99, wherein thecatalyst is free of tin.

Embodiment 101 is the method of any of embodiments 62 to 100, whereinthe catalyst contains bismuth.

Embodiment 102 is the method of any of embodiments 62 to 101, whereinthe polyurethane (meth)acrylate polymer has a weight average molecularweight of 6,000 g/mol to 35,000 g/mol.

Embodiment 103 is the method of any of embodiments 62 to 102, whereinthe photopolymerizable composition further includes a difunctionalmonomer in an amount of up to 15 wt. %, based on the total weight of thephotopolymerizable composition.

Embodiment 104 is the method of embodiment 103, wherein the difunctionalmonomer includes a compound of Formula (X):H₂C═C(R₃)C(═O)X-Q-O—C(═O)NH—R_(d)i-NHC(═O)—O-Q-XC(═O)(R₃)═CH₂ (X),wherein R_(d), is the residue of a diisocyanate and R₃ is as defined forFormula (II).

Embodiment 105 is the method of embodiment 103, wherein the difunctionalmonomer includes a compound of Formula (XI):H₂C═C(R₃)C(═O)—O-Q-NH—C(═O)—(O—R₁—O—C(═O))_(m)—O—R₂—O—C(═O)NH-Q-O—C(═O)C(R₃)═CH₂(XI) wherein Q and R₃ are as defined for Formula (II) and R₁ and R₂ areas defined for Formula (I).

Embodiment 106 is the method of any of embodiments 62 to 105, wherein aratio of the isocyanate to the polycarbonate diol ranges from 4 molarequivalents of the isocyanate to 1 molar equivalent of the alcohol ofthe polycarbonate diol, to 4 molar equivalents of the isocyanate to 3molar equivalents of the alcohol of the polycarbonate diol.

Embodiment 107 is the method of embodiment 106, wherein the ratio of theisocyanate to the polycarbonate diol is 4 molar equivalents ofisocyanate to 2 molar equivalents of the alcohol of the polycarbonatediol.

Embodiment 108 is the method of any of embodiments 62 to 107, wherein aratio of the isocyanate to the (meth)acrylate mono-ol ranges from 4molar equivalents of the isocyanate to 3 molar equivalents of the(meth)acrylate mono-ol to 4 molar equivalents of the isocyanate to 1molar equivalent of the (meth)acrylate mono-ol.

Embodiment 109 is the method of any of embodiments 62 to 108, wherein aratio of the isocyanate to the (meth)acrylate mono-ol is 4 molarequivalents of the isocyanate to 2 molar equivalents of the(meth)acrylate mono-ol.

Embodiment 110 is the method of any of embodiments 62 to 109, wherein aratio of the polycarbonate diol to the (meth)acrylate mono-ol rangesfrom 1 molar equivalent of the alcohol of the polycarbonate diol to 3molar equivalents of the (meth)acrylate mono-ol, to 3 molar equivalentsof the alcohol of the polycarbonate diol to 1 molar equivalents of the(meth)acrylate mono-ol.

Embodiment 111 is the method of any of embodiments 62 to 110, wherein aratio of the polycarbonate diol to the (meth)acrylate mono-ol is 1 molarequivalent of the alcohol of the polycarbonate diol to 1 molarequivalent of the (meth)acrylate mono-ol.

Embodiment 112 is the method of any of embodiments 62 to 111, whereinthe polyurethane (meth)acrylate is of Formula (VI):

(A)_(p)-Q-OC(O)NH—R_(dh)—NH—C(O)—[O—R_(dOH)—OC(O)NH—R_(dh)—NH—C(O)]_(r)—O-Q-(A)_(p)  (VI)

wherein, A has the formula —OC(═O)C(R₃)═CH₂ wherein R₃ is an alkyl of 1to 4 carbon atoms (e.g. methyl) or H, p is 1 or 2, Q is a polyvalentorganic linking group as described above, Rai is the residue of adiisocyanate, R_(dOH) is the residue of a polycarbonate polyol, and raverages from 1 to 15.

Embodiment 113 is the method of any of embodiments 62 to 112, thephotopolymerizable composition further includes a second polymerizationreaction product of components. The components include 1) an isocyanatefunctional (meth)acrylate compound of the Formula (VII): (A)_(p)-Q-NCO(VII), wherein A, p, and Q are as defined for Formula (II); 2) apolycarbonate diol of Formula (I): H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and3) a catalyst. Each of R₁ in each (O—R₁—O—C(═O)) repeat unit and each R₂are independently an aliphatic, cycloaliphatic, oraliphatic/cycloaliphatic alkylene group and an average number of carbonatoms in a combination of all the R₁ and R₂ groups is 4 to 10, and m is2 to 23.

Embodiment 114 is the method of embodiment 113, wherein the secondpolymerization reaction product includes a compound of Formula (VIII):

(H₂C═C(R₃)C(═O)—O)_(p)—O-Q-NH—C(═O)—(O—R₁—O—C(═O))_(m)—O—R₂—O—C(═O)NH-Q-(O—C(═O)(R₃)C═CH₂)_(p)  (VIII).

Q, p, and R₃ are as defined for Formula (II) and R₁ and R₂ are asdefined for Formula (I).

Embodiment 115 is the method of embodiment 114, wherein the compound ofFormula (VIII) is a compound of Formula (IX):

wherein n is about 6.7 for a 1000 molecular weight polycarbonate diolbased on hexane diol.

Embodiment 116 is the method of any of embodiments 62 to 115, wherein acured homopolymer of the monofunctional (meth)acrylate monomer has aT_(g) of 100° C. or greater.

Embodiment 117 is the method of any of embodiments 62 to 116, whereinthe cured homopolymer of the monofunctional (meth)acrylate monomer has aT_(g) of 170° C. or greater or 180° C. or greater.

Embodiment 118 is the method of any of embodiments 62 to 117, whereinthe monofunctional acrylate monomer includes a cycloaliphaticmonofunctional (meth)acrylate.

Embodiment 119 is the method of any of embodiments 62 to 118, whereinthe monofunctional acrylate monomer includes isobornyl methacrylate.

Embodiment 120 is the method of any of embodiments 62 to 119, whereinthe orthodontic article exhibits an initial relaxation modulus of 100megapascals (MPa) or greater measured at 2% strain at 37° C.

Embodiment 121 is the method of any of embodiments 62 to 120, whereinthe orthodontic article exhibits a percent loss of relaxation modulus of70% or less.

Embodiment 122 is the method of any of claims 62 to 121, wherein theorthodontic article exhibits a percent loss of relaxation modulus of 40%or less.

Embodiment 123 is the method of any of embodiments 62 to 122, whereinthe orthodontic article exhibits a relaxation modulus of 100 MPa orgreater.

Embodiment 124 is the method of any of embodiments 62 to 123, whereinthe orthodontic article exhibits an elongation at break of a printedarticle of 20% or greater.

Embodiment 125 is the method of any of embodiments 62 to 124, whereinthe orthodontic article exhibits an elongation at break of a printedarticle of 70% or greater.

Embodiment 126 is the method of any of embodiments 62 to 125, whereinthe orthodontic article exhibits a tensile strength at yield of 14 MPaor greater.

Embodiment 127 is the method of any of embodiments 62 to 126, whereinthe orthodontic article exhibits a tensile strength at yield of 25 MPaor greater

Embodiment 128 is the method of any of embodiments 62 to 127, whereinthe orthodontic article contains 1 wt. % or less extractable components.

Embodiment 129 is the method of any of embodiments 62 to 128, whereinthe orthodontic article exhibits a peak in loss modulus of 20° C. orless.

Embodiment 130 is the method of embodiment 129, exhibiting a tan deltapeak of 80° C. or greater.

Embodiment 131 is the method of any of embodiments 62 to 130, whereinthe orthodontic article includes a dental tray, a retainer, or analigner.

Embodiment 132 is the method of any of embodiments 62 to 131, whereinthe orthodontic article includes an aligner.

Embodiment 133 is a compound of Formula (V):

Embodiment 134 is an orthodontic article including a polymerizedreaction product of a photopolymerizable composition. Thephotopolymerizable composition includes i) a monofunctional(meth)acrylate monomer whose cured homopolymer has a T_(g) of 90° C. orgreater; ii) a photoinitiator; iii) a UV absorber comprising a compoundof Formula (V)

andiv) a polymerization reaction product of components. The componentsinclude 1) an isocyanate; 2) a (meth)acrylate mono-ol; 3) apolycarbonate diol of Formula (I): H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and4) a catalyst. Each of R₁ in each (O—R₁—O—C(═O)) repeat unit and each R₂are independently an aliphatic, cycloaliphatic, oraliphatic/cycloaliphatic alkylene group and an average number of carbonatoms in a combination of all the R₁ and R₂ groups is 4 to 10, and m is2 to 23. The polymerized reaction product of the photopolymerizablecomposition has a shape of the orthodontic article.

Embodiment 135 is a method of making an orthodontic article, the methodincluding a) obtaining a photopolymerizable composition; b) selectivelycuring the photopolymerizable composition; and c) repeating steps a) andb) to form multiple layers and create the orthodontic article. Thephotopolymerizable composition includes i) a monofunctional(meth)acrylate monomer whose cured homopolymer has a T_(g) of 90° C. orgreater; ii) a photoinitiator; iii) a UV absorber comprising a compoundof Formula (V)

andiv) a polymerization reaction product of components. The componentsinclude 1) an isocyanate; 2) a (meth)acrylate mono-ol; 3) apolycarbonate diol of Formula (I): H(O—R₁—O—C(═O))_(m)O—R₂—OH (I); and4) a catalyst. Each of R₁ in each (O—R₁—O—C(═O)) repeat unit and each R₂are independently an aliphatic, cycloaliphatic, oraliphatic/cycloaliphatic alkylene group and an average number of carbonatoms in a combination of all the R₁ and R₂ groups is 4 to 10, and m is2 to 23. The polymerized reaction product of the photopolymerizablecomposition has a shape of the orthodontic article.

Embodiment 136 is a non-transitory machine readable medium comprisingdata representing a three-dimensional model of an orthodontic article,when accessed by one or more processors interfacing with a 3D printer,causes the 3D printer to create an orthodontic article comprising areaction product of a photopolymerizable composition. Thephotopolymerizable composition includes i) a monofunctional(meth)acrylate monomer whose cured homopolymer has a T_(g) of 90° C. orgreater; ii) a photoinitiator; and iii) a polymerization reactionproduct of components. The components include 1) an isocyanate; 2) a(meth)acrylate mono-ol; 3) a polycarbonate diol of Formula (I):H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 4) a catalyst. Each of R₁ in each(O—R₁—O—C(═O)) repeat unit and each R₂ are independently an aliphatic,cycloaliphatic, or aliphatic/cycloaliphatic alkylene group and anaverage of carbon atoms in a combination of all the R₁ and R₂ groups is4 to 10, and m is 2 to 23. The polymerized reaction product of thephotopolymerizable composition has a shape of the orthodontic article.

Embodiment 137 is a method including a) retrieving, from anon-transitory machine readable medium, data representing a 3D model ofan article; b) executing, by one or more processors, a 3D printingapplication interfacing with a manufacturing device using the data; andc) generating, by the manufacturing device, a physical object of theorthodontic article. The orthodontic article includes a reaction productof a photopolymerizable composition. The photopolymerizable compositionincludes i) a monofunctional (meth)acrylate monomer whose curedhomopolymer has a T_(g) of 90° C. or greater; ii) a photoinitiator; andiii) a polymerization reaction product of components. The componentsinclude 1) an isocyanate; 2) a (meth)acrylate mono-ol; 3) apolycarbonate diol of Formula (I): H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and4) a catalyst. Each of R₁ in each (O—R₁—O—C(═O)) repeat unit and each R₂are independently an aliphatic, cycloaliphatic, oraliphatic/cycloaliphatic alkylene group and an average number of carbonatoms in a combination of all the R₁ and R₂ groups is 4 to 10, and m is2 to 23. The polymerized reaction product of the photopolymerizablecomposition has a shape of the orthodontic article.

Embodiment 138 is a method including a) receiving, by a manufacturingdevice having one or more processors, a digital object comprising dataspecifying a plurality of layers of an orthodontic article; and b)generating, with the manufacturing device by an additive manufacturingprocess, the orthodontic article based on the digital object. Theorthodontic article includes a reaction product of a photopolymerizablecomposition. The photopolymerizable composition includes i) amonofunctional (meth)acrylate monomer whose cured homopolymer has aT_(g) of 90° C. or greater; ii) a photoinitiator; and iii) apolymerization reaction product of components. The components include 1)an isocyanate; 2) a (meth)acrylate mono-ol; 3) a polycarbonate diol ofFormula (I): H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 4) a catalyst. Each ofR₁ in each (O—R₁—O—C(═O)) repeat unit and each R₂ are independently analiphatic, cycloaliphatic, or aliphatic/cycloaliphatic alkylene groupand an average number of carbon atoms in a combination of all the R₁ andR₂ groups is 4 to 10, and m is 2 to 23. The polymerized reaction productof the photopolymerizable composition has a shape of the orthodonticarticle.

Embodiment 139 is a system including a) a display that displays a 3Dmodel of an orthodontic article; and b) one or more processors that, inresponse to the 3D model selected by a user, cause a 3D printer tocreate a physical object of an orthodontic article. The orthodonticarticle includes a reaction product of a photopolymerizable composition.The photopolymerizable composition includes i) a monofunctional(meth)acrylate monomer whose cured homopolymer has a T_(g) of 90° C. orgreater; ii) a photoinitiator; and iii) a polymerization reactionproduct of components. The components include 1) an isocyanate; 2) a(meth)acrylate mono-ol; 3) a polycarbonate diol of Formula (I):H(O—R₁—O—C(═O))_(m)—O—R₂—OH (I); and 4) a catalyst. Each of R₁ in each(O—R₁—O—C(═O)) repeat unit and each R₂ are independently an aliphatic,cycloaliphatic, or aliphatic/cycloaliphatic alkylene group and anaverage number of carbon atoms in a combination of all the R₁ and R₂groups is 4 to 10, and m is 2 to 23. The polymerized reaction product ofthe photopolymerizable composition has a shape of the orthodonticarticle.

Embodiment 140 is the article of any of embodiments 1 to 61, wherein thephotopolymerizable composition comprises at least one hydrophilicmonomer or polymer having a log P of less than 3, present in an amountof 1% to 25% by weight, based on the total weight of thephotopolymerizable composition.

Embodiment 141 is the article of embodiment 140, wherein thephotopolymerizable composition comprises at least one monofunctional(meth)acrylate monomer whose homopolymer has a T_(g) of 150° C. orgreater in an amount of 20% by weight or greater, based on the totalweight of the photopolymerizable composition.

Embodiment 142 is the method of any of embodiments 62 to 131, whereinthe photopolymerizable composition comprises at least one hydrophilicmonomer or polymer having a log P of less than 3, present in an amountof 1% to 25% by weight, based on the total weight of thephotopolymerizable composition.

Embodiment 143 is the method of embodiment 142, wherein thephotopolymerizable composition comprises at least one monofunctional(meth)acrylate monomer whose homopolymer has a T_(g) of 150° C. orgreater in an amount of 20% by weight or greater, based on the totalweight of the photopolymerizable composition.

EXAMPLES

Objects and advantages of this disclosure are further illustrated by thefollowing examples, but the particular materials and amounts thereofrecited in these examples, as well as other conditions and details,should not be construed to unduly limit this disclosure.

Materials

Unless otherwise noted, all parts, percentages, ratios, etc. in theexamples and the rest of the specification are by weight. The MaterialsTable (below) lists materials used in the examples and their sources.

Materials Table Material designation Description 1-Adamantanol Obtainedfrom TCI America, Portland, OR. 212-20 A polycarbonate diol of about1500 MW made with CO₂ and propylene oxide obtained as “CONVERGE POLYOL212-20” from Aramco, Dhahran, Saudi Arabia. 4-chloro-1,8- Obtained fromAlfa Aesar, Haverhill, MA. naphthalic anhydride 4-hydroxy-TEMPO4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl, obtained from SigmaAldrich, St. Louis, MO. 4-tert- 4-tert-butylcyclohexanol, mixture ofisomers, obtained from TCI butylcyclohexanol America, Portland, OR.Acetonitrile Omnisolv HPLC grade obtained from EMD Millipore, a part ofMerck KGaA, Darmstadt, Germany. Acrylic acid Obtained from Alfa Aesar,Haverill, MA. Acryloyl chloride Obtained from Sigma-Aldrich ChemicalCompany, St. Louis, MO. Ammonium formate Obtained as a 5 M aqueoussolution from Agilent Technologies, Waldbronn, Germany. AnhydrousObtained from EMD Millipore, a part of Merck KGaA. magnesium sulfate BHT2,6-di-t-butyl-4-methylphenol obtained from Alfa Aesar, Haverhill, MA.BiN Bismuth neodecanoate obtained from Sigma-Aldrich, St. Louis, MO. CXP-2613 A polycarbonate diol of about 2000 MW of what is believed tohave about a 75:25 mole ratio of butane diol:hexane diol, obtained as“DESMOPHEN C XP-2613” from Covestro LLC., Leverkusen, Germany. C-1090 Apolycarbonate diol of about 1000 MW made with about a 9:1 mole ratio of3-methyl-1,5-pentanediol (MPD): hexane diol (HD), (i.e., 90% MPD,)obtained as “KURARAY POLYOL C-1090” from Kuraray Co. Ltd., Tokyo, Japan.C-2050 A polycarbonate diol of about 2000 MW made with about a 50%(i.e., 5:5) mole ratio of (MPD): (HD), obtained as “KURARAY POLYOL C-2050” from Kuraray Co. Ltd. C-2090 A polycarbonate diol of about 2000 MWmade with about a 9:1 mole ratio of (MPD): (HD), obtained as “KURARAYPOLYOL C-2090” from Kuraray Co. Ltd. C-2100 A polycarbonate diol ofabout 1000 MW that it is believed uses HD as the diol, obtained as“DESMOPHEN C-2100” from Covestro LLC. C-2200 A polycarbonate diol ofabout 2000 MW that it is believed uses HD as the diol, obtained as“DESMOPHEN C-2200” from Covestro LLC. C-3090 A polycarbonate diol ofabout 3000 MW made with about a 9:1 mole ratio of (MPD): (HD), obtainedas “KURARAY POLYOL C-3090” from Kuraray Co. Ltd. C-590 A polycarbonatediol of about 500 MW made with about a 9:1 mole ratio of (MPD): (HD)obtained as “KURARAY POLYOL C-590” from Kuraray Co. Ltd. CEA2-Carboxyethyl acrylate, obtained from Sigma-Aldrich, St. Louis, MO.Chloroform Obtained from EMD Millipore, a part of Merck KGaA, Darmstadt,Germany. CHMA Cyclohexyl methacrylate, obtained from Alfa Aesar,Haverhill, MA. DBTDL Dibutyltin diacrylate, obtained from Sigma-Aldrich,St. Louis, MO. DDDMA 1,12-dodecanediol dimethacrylate obtained as“SR262” from Sartomer, Exton, PA. Desmodur I (IPDI) Isophoronediisocyanate, under trade designation “DESMODUR I” equivalent weight111.11, molecular weight 222.22 g/mole, from Covestro LLC. Desmodur WHydrogenated methylene diisocyanate, under trade designation (H12MDI)“DESMODUR W”, equivalent weight 131.25, molecular weight 262.5 g/mole,from Covestro LLC. DiCPMA Dicyclopentanyl methacrylate Obtained from TCIAmerica, Portland, OR. DMAP 4-dimethylaminopyridine, obtained from AlfaAesar, Haverhill, MA. EHMA 2-Ethyl hexyl methacrylate, obtained fromAlfa Aesar. Ethanol Obtained from Spectrum Chemicals, New Brunswick, NJ.Ethanolamine Obtained from Sigma Aldrich. Ethyl acetate Obtained fromEMD Millipore, a part of Merck KGaA. Exothane-10 A urethane(meth)acrylate oligomer comprising a polyethylene oxide diol of about400 MW, obtained as “EXOTHANE-10” from Esstech Inc., Essington, PA.Exothane-108 A urethane (meth)acrylate oligomer comprising apolytetramethylene oxide diol of about 650 MW, obtained as“EXOTHANE-108” from Esstech Inc. G-AC-MAC Glycerol acrylate methacrylate( 1-(acryloyloxy)-3-(methacryloyloxy)-2- propanol, CAS 1709-71-3),obtained from TCI America, Portland, OR. HCl Hydrochloric acid, obtainedfrom Sigma Aldrich. HDDMA 1,6-Hexanediol dimethacrylate (SR239),obtained from Sartomer. HDI 1,6-diisocyanatohexane, equivalent weight84.1, molecular weight 168.2, available under trade designation“DESMODUR H”, from Covestro LLC. HEA Hydroxyethyl acrylate, obtainedfrom Alfa Aesar. HEMA Hydroxyethyl methacrylate, obtained from TCIAmerica, Portland, OR. Heptane Heptane (Ultra resi-analyzed) wasobtained from Avantor, Center Valley, PA. Hydroquinone Obtained fromAlfa Aesar. IBOA Isobornyl acrylate, obtained from Alfa Aesar. IBOMAIsobornyl methacrylate obtained as “SR423A” from Sartomer. IEMIsocyanatoethyl methacrylate, MW 155.15, available under the tradedesignation “KARENZ MOI,” from Showa Denko. IEM-EO Isocyanatoethoxyethylmethacrylate, MW 199.2, available under the trade designation “KARENZMOI-EG,” from Showa Denko. iPrOH Isopropyl alcohol, obtained from EMDMillipore, a part of Merck KGaA. KOH Potassium hydroxide, obtained fromSigma Aldrich. MDI Product trade designation “MONDUR MLQ,” anapproximate 80:20 mixture of 4,4′ and 2,4′ diphenylmethane diisocyanate,equivalent weight 125.125, molecular weight 250.25, from Covestro LLC.MeOH Methanol, obtained from EMD Millipore, a part of Merck KGaA.Methacrylic acid Obtained from Sigma Aldrich. Methacrylic Obtained fromSigma Aldrich. anhydride Na₂CO₃ Sodium Carbonate, obtained from SigmaAldrich. NL2030B A polycarbonate diol of about 2000 MW made with about a3:7 mole ratio of neopentyl glycol:butane diol, obtained as “NL2030B”from Mitsubishi Chemical Company, Tokyo, JP. NL2005B A polycarbonatediol of about 2000 MW made with about a 5:95 mole ratio of neopentylglycol:butane diol, obtained as “NL2005B” from Mitsubishi ChemicalCompany. NL2010DB A polycarbonate diol of about 2000 MW made with abouta 10:90 mole ratio of 1,10-decane diol:butane diol, obtained as“NL2010B” from Mitsubishi Chemical Company. NVP 1-vinyl-2-pyrolidone,obtained from TCI Chemicals, Portland, OR. Omnirad 3792-Dimethylamino-2-(4-methyl-benzy1)-1-(4-morpholin-4-yl-pheny1)-butan-1-one, photoinitiator, obtained from IGM Resins, Charlotte, NC.P-1020 A 3-methyl-1,5-pentane diol terephthalate diol of about 1000 MWobtained as “KURARAY POLYOL P-1020” from Kuraray. PBS Phosphate bufferedsaline (PBS, 10X), pH =7.4, obtained from Alfa Aesar. PEG600DMAPolyethylene glycol 600 dimethacrylate, obtained from Sartomer. PEMA2-Phenoxy ethyl methacrylate (“SR340”), obtained from Sartomer.Petroleum ether Obtained from EMD Millipore, a part of Merck KGaA.Phenothiazine Obtained from TCI America. Propylene Obtained from AlfaAesar. Carbonate PTMO-2000 A poly(tetramethylene oxide) diol of about2000 MW, obtained as “POLYTHF 1000” polyether from BASF, Florham Park,NJ. p-toluenesulfonic Obtained from TCI, America. acid Sodiumbicarbonate Obtained from EMD Millipore, a part of Merck KGaA. Sulfuricacid Obtained from EMD Millipore, a part of Merck KGaA. TetrahydrofuranOmnisolv HPLC grade from EMD Millipore, a part of Merck KGaA. THFMATetrahydrofurfuryl methacrylate, obtained from Sartomer. Tinuvin 326Phenol, 2-(5-chloro-2H-benzotriazol-2-y1)-6-(1,1-dimethylethyl)-4-methyl, UV-absorber, obtained from BASF. TMXDI1,3-Bis(1-isocyanato-1-methylethyl)benzene, equivalent weight 122.15,molecular weight 244.3, from Sigma-Aldrich. TPO2,4,6-trimethylbenzoyldiphenylphosphine oxide photoinitiator obtained as“IRGACURE TPO” from BASF. Triethylamine Obtained from EMD Millipore, apart of Merck KGaA. TMCHMA 3,3,5-trimethylcylohexanemethacrylate,obtained from Sartomer. XK-672 Zn based catalyst obtained as “K-KATXK-672” from King Industries, Norwalk, CT.

Preparatory Examples Preparation of Naphthalimide Acrylate (NapA)

To a 1 L three-neck round-bottom flask was added 4-chloronaphthalicanhydride (100.0 g, 0.4299 moles, 1.0 equiv.), ethanolamine (26.26 g,0.4299 moles, 1.0 equiv.), and iPrOH (516.7 g). The flask was outfittedwith a temperature probe, overhead stirrer, and reflux condenser. Thereaction mixture was heated to 80° C. with stirring for 6 hours, thencooled to 10° C. with an ice bath. The resulting yellow solid wascollected via filtration and stirred with a mixture of water (300 g),iPrOH (300 g), and concentrated HCl (10 g). The resulting solid wasfiltered and washed with water/iPrOH (1:1, 500 g) and allowed to airdry. This afforded alcohol 2 (102 g, 86%).

To a 2 L three-neck round-bottom flask was added alcohol 2 (100.0 g,0.3627 moles, 1.0 equiv.), KOH (40.71 g, 0.7255 moles, 2.0 equiv.), andmethanol (581 g). The flask was outfitted with a temperature probe,overhead stirrer, and reflux condenser. The reaction mixture was heatedto 65° C. with stirring for 36 hours, then cooled to 10° C. with an icebath. The resulting yellow solid was collected via filtration andstirred with a mixture of water (300 g), MeOH (300 g), and concentratedHCl (10 g). The resulting solid was filtered and washed with water/MeOH(1:1, 600 g) and allowed to air dry. This afforded alcohol 3 (86.5 g,88%).

To a 1 L 3-neck round-bottom flask was added alcohol 3 (80.00 g, 0.2949moles, 1.0 equiv.), chloroform (704 g), and triethylamine (35.81 g,0.3539 moles, 1.2 equiv.). The flask was outfitted with a Claisenadapter, overhead stirrer, and a pressure-equalizing addition funnel.The Claisen adapter was outfitted with a temperature probe and a refluxcondenser. The reaction mixture was stirred and heated to 40° C.Acryloyl chloride (29.36 g, 0.3244 moles, 1.1 equiv.) was added dropwisevia the addition funnel such that the reaction temperature did not riseabove 45° C. After addition was complete, the reaction was stirred for30 minutes. Triethylamine (6.00 g, 0.0593 moles, 0.2 equiv.) was added,followed by acryloyl chloride (5.00 g, 0.0552 moles, 0.19 equiv.)dropwise. The reaction was stirred for an additional 30 minutes at 40°C. Next, the reaction flask was outfitted with a distillation head,condenser, and receiving flask. The reaction mixture was heated to stripmost of the chloroform. EtOH (500 g) was added, and the strip continueduntil the distillation head temperature reached 78° C. The reactionmixture was cooled to 10° C. with an ice bath and filtered. Theresulting solid was washed with water/HCl (10:1, 500 mL), water/Na₂CO₃(10:1, 500 mL), and water/EtOH (1:1, 500 mL). The solid was allowed todry to afford the product 4 as a pale yellow solid (92.5 g, 96%).

Preparation of Adamantyl-1-methacrylate (AdMA)

A 2 L, 3 neck round-bottom flask was fitted with a dean-stark trap witha condenser, magnetic stir bar, and a thermometer. 1-Adamantanol (252 g1.650 mol), hydroquinone (0.3 g), methacrylic acid (455 g, 5.28 mmol),and methylcyclohexane (400 g) were added and the mixture was stirred.Sulfuric acid (10.5 g) was then added to the mixture, and then dry airwas slowly bubbled into the mixture. The mixture was heated to refluxunder constant bubbling of air for 26 hours, during which time thereaction product water was removed using the trap. The mixture was thencooled to room temperature, and slowly added to a mechanically stirred,ice-bath cooled mixture of 350 g KOH (6.2 mol) in 1000 g of deionizedwater and 500 g hexanes. After the addition was complete, the resultingmixture was separated using a separatory funnel, and extracted 1×500 mLhexanes. The combined organic extracts were washed with a saturatedaqueous sodium bicarbonate solution, and then 20 mg of phenothiazine wasadded to the organic phase. This was then dried over anhydrous magnesiumsulfate, filtered, and concentrated by rotary evaporation. Theconcentrate was then distilled under vacuum (BP=87-90° C., 0.3 torr),where the receiver flask contained 15 mg of 4-hydroxy-TEMPO, and 320 gof liquid was obtained. BHT (48 mg) was then added and dry air wasbubbled into the clear product for 30 seconds before storage. ¹H NMR:5.99 (m, 1H), 5.45 (m, 1H), 2.14 (m, 9H), 1.87 (m, 3H), 1.64 (m, 6H).¹³C NMR: 168.5, 138.1, 124.3, 80.4, 41.3, 36.3, 30.9, 18.4. Purity byGC=98.4%.

Characterization of the Above Material by Nuclear Magnetic Resonance(NMR) Spectroscopy

An Ultrashield 500 Plus FT NMR instrument from Bruker (Billerica, Mass.)was used to acquire ¹H NMR (500 MHz) and ¹³C NMR (125 MHz) spectra.Chemical shifts (6) are reported in ppm relative to CDCl₃. Abbreviationsfor splitting patterns are as follows; s (singlet); d (doublet); t(triplet); q (quartet); m (multiplet); br (broad); app (apparent) andcombinations of these abbreviations.

Preparation of 4-tert-butylcyclohexyl methacrylate (mixture cis/trans)(tBuCHMA)

A 2 L, 3 neck round-bottom flask was fitted with a 250 mL additionfunnel, magnetic stir bar, and a thermometer. 4-tertbutylcyclohexanol(150 g, 960 mmol), dichloromethane (600 g), triethylamine (178 g, 1760mmol), and DMAP (6.4 g, 52 mmol) were added to the flask, and thenmethacrylic anhydride (263 g, 1710 mmol) was added dropwise keeping thetemperature below 35° C. This mixture was stirred at room temperaturefor 24 hours, and then 150 mL water was added and stirred overnight.Dichloromethane (500 g) was then added, and the organic phase was washedwith 200 mL water, 200 mL of 0.1 M HCl, and 200 mL saturated sodiumbicarbonate. The organic phase was dried over anhydrous magnesiumsulfate and 20 mg phenothiazine was added. This was filtered andconcentrated by rotary evaporation. The concentrate was then distilledunder vacuum (BP=73-90° C., 0.3 torr), where the receiver flaskcontained 7 mg of 4-hydroxy-TEMPO, and 170 g of liquid was obtained. BHT(26 mg) was then added and dry air was bubbled into the clear productfor 30 seconds before storage. ¹H NMR was consistent with a mixture of72% trans and 28% cis isomer as described in Macromolecules, 1993, 26,1659-1665. GC analysis showed a total of 96% of the two isomers with aratio of 73% trans/27% cis.

Characterization of the Above Material by Gas Chromatography (GC)

Sample purity and product ratios were determined by gas chromatography(GC) and was performed using a Hewlett Packard (Palo Alto, Calif.) 6890Series Plus gas chromatograph with a flame ionization detector and HPG1530A digital integrator. Sample injection was done with a 7683 seriesinjector in conjunction with an injection volume of 2 microliters,injection port at a temperature of 250° C., and a split ratio of 20:1. A30 m×0.53 mm×5 micrometer column obtained under the trade designation“RESTEX RTX-1” from Restek Corp. (Bellefonte, Pa.) was utilized with aflow rate of 12.4 mL/min He as the carrier gas with a temperatureprogram of 50° C. to 230° C. at 15° C./min; 230° C. to 280° C. at 50°C./min; then hold at 280° C. for 2 min.

Preparation of diol diacrylates Preparation of C-590 diol diacrylate

C-590 diol (50 g, 90.79 mmol;) and acrylic acid (19.8 g, 275 mmol,) andp-toluenesulfonic acid (1.96 g, 11.3 mmol,) were charged into a 250 mL3-neck flask equipped with a magnetic stirring bar, a thermocouple and acondenser. The mixture was heated at 85° C. Vacuum (15-20 torr) wasapplied for 2 minutes every 15-20 minutes in order to remove any formedwater from the reaction. This was repeated for 4 hours at which timethere were no signs of H₂O forming or condensing on the flask walls. Theheat was turned off. After cooling to room temperature, the mixture wasdissolved in a 130 mL ethyl acetate/petroleum ether mixture (10:3ratio). The mixture was extracted with 10% aqueous NaOH (100 mL) thenH₂O (200 mL). The organic layer was dried (over Na₂SO₄), thenconcentrated to give a clear liquid with 91% yield.

Preparation of C-590 diol dimethacrylate (C-590 diol MA)

This material was prepared following the procedure described above forpreparation of C-590 diol diacrylate, except that methacrylic acid wasused instead of acrylic acid. The product was isolated as a lowviscosity liquid in 88-93% yield.

Preparation of C-2050 diol dimethacrylate (C-2050 diol MA)

This material was prepared following the procedure described above forpreparation of C-590 diol diacrylate, except that methacrylic acid wasused instead of acrylic acid and C-2050 diol was used instead of C-590diol.

Preparation of Polycarbonate Diol Based Urethane (Meth)acrylates

The urethane acrylates are of three main types:

-   -   1) Polycarbonate diols reacted with diisocyanates capped with        (meth)acrylate mono-ols such as HEA and HEMA. Below is an        idealized structure of such a material, illustrated with a        hexane diol based polycarbonate diol:

-   -   2) Polycarbonate diols capped with isocyanate-(meth)acrylates,        illustrated with a hexane diol based polycarbonate diol and IEM:

-   -   3) Diisocyanates capped with (meth)acrylate mono-ols:

Type 1: 4 IPDI/2 C-2050/2 HEMA (PE-1)

A 1 L three-necked round-bottom flask was charged with 514.75 g C-2050(0.52285 eq, 984.5 hydroxide equivalent weight (OH EW)), heated to about45° C., then were added 116.19 g IPDI (1.0457 eq), 0.280 g BHT (400ppm), and 0.175 DBTDL (250 ppm). The reaction was heated under dry airto an internal setpoint of 105° C. (temperature reached at about 20min). At 1 hour and 20 minutes 69.06 g HEMA (0.5307 eq, 130.14 MW, a1.5% excess) was added via an addition funnel at a steady rate over 1hour and 10 minutes. The reaction was heated for about 2.5 hours at 105°C., then an aliquot was checked by Fourier transform infraredspectroscopy (FTIR) and found to have no −NCO peak at 2265 cm¹ and theproduct was isolated as a clear, viscous material.

Type 2: C-2050/2 IEM (PE-2)

A 1 L three-necked round-bottom flask was charged with 431.93 g C-2050(0.43873 eq, 984.5 OH EW), 0.200 g BHT (400 ppm), and 0.125 g DBTDL (250ppm) and heated to an internal temperature of about 60° C. under dryair. Then 68.07 g IEM (0.43873 eq, 155.15 MW) was added via an additionfunnel over about 1 hour and 20 minutes. At 1 hour and 30 minutes analiquot was checked by FTIR and found to have no −NCO peak at 2265 cm⁻¹.At 1 hour and 38 minutes 1.32 g more IEM was added, and an aliquot waschecked by FTIR and found to have no −NCO peak at 2265 cm⁻¹. At 4 hoursinto the reaction, the reaction was stopped and the product was isolatedas a clear, viscous material.

Type 3: IPDI/HEMA (PE-3)

A 1 L three-necked round-bottom flask was charged with 319.80 g IPDI(2.878 eq), 0.280 g BHT, and 0.175 g bismuth neodecanoate (250 ppm basedon solids) and heated to an internal temperature of about 55° C. underdry air. Then 380.20 g (2.921 eq) HEMA was added over 1 hour and 45minutes, with the internal temperature rising to a maximum of 90° C. At2 hours and 25 minutes an aliquot was checked by FTIR and found to haveno −NCO peak at 2265 cm⁻¹.

The samples in Table 2 below were prepared by methods according to thoseof Types 1-3 described above, using the amounts and types of materialsindicated in the table.

TABLE 2 Preparative Examples of Polycarbonate Diol Based Polyurethane(Meth) Acrylates Isocyanate Diol (meth)-acrylate mono-ol Catalyst BHTSample Designation Type g Type g OH EW Type g Type g g PE-4 4 IPDI/2P-1020/2 HEMA IPDI  39.02 P-1020  87.79  500 HEMA  23.19 DBTDL 0.075 0PE-5 4 IPDI/2 C-2050/2 HEMA IPDI  82.99 C-2050  367.68  984.2 HEMA 49.33 DBTDL 0.125 0.200 PE-6 4 H12MDI/2 C-2050/2 HEMA H12MDI  95.17C-1090  356.94  984.2 HEMA  47.89 DBTDL 0.125 0.200 PE-7 4 IPDI/2C-2050/2 HEMA IPDI  82.99 C-2050  367.68  984.2 HEMA  49.33 DBTDL 0.1250.200 PE-8 4 IPDI/2 C-2020/2 HEMA IPDI  83.81 C-2020  366.37  971.42HEMA  49.82 DBTDL 0.125 0.200 PE-9 C-2090/IEM IEM  69.63 C-2090  430.37 959 — DBTDL 0.125 0.200 PE-10 C-2090/IEM-EO IEM-EO  86.00 C-2050 414.00  959 — DBTDL 0.125 0.200 PE-11 C-2050/IEM IEM  18.91 C-2050 120.00  984.2 — DBTDL 0.035 0.056 PE-12 C-2200/IEM IEM  68.86 C-2200 431.14  971.42 — DBTDL 0.125 0.200 PE-13 4 IPDI/2 C-3090/2 HEMA IPDI 60.57 C-3090  403.43 1480.21 HEMA  36.00 DBTDL 0.125 0.200 PE-14C-3090/IEM IEM  47.44 C-3090  452.56 1480.21 — — DBTDL 0.125 0.200 PE-15C-1090/IEM IEM 117.78 C-1090  382.22  503.5 — — DBTDL 0.125 0.200 PE-16C-590/IEM IEM 192.83 C-590  307.17  247.14 — — DBTDL 0.125 0.200 PE-17 4IPDI/2 212-20/2 HEMA IPDI  98.96 212-20  342.22  768.49 HEMA  58.82DBTDL 0.125 0.200 PE-18 4 IPDI/2 PTMO-2000/2 IPDI  82.82 PTMO-2000 367.95  997.0 HEMA  49.23 DBTDL 0.125 0.200 HEMA PE-19 4 IPDI/1.5C-2050/2.5 HEMA IPDI  98.70 C-2050  327.96  984.2 HEMA  73.34 DBTDL0.125 0.200 PE-20 4 IPDI/2.5 C-2050/1.5 HEMA IPDI  71.6 C-2050  396.49 984.2 HEMA  31.92 DBTDL 0.125 0.200 PE-21 4 TMXDI/2 C-2050/2 HEMA TMXDI 89.78 C-2050  361.68  984.2 HEMA  48.54 DBTDL 0.125 0.200 PE-22 4IPDI/2 C-2050/2 HEA IPDI 117.46 C-2050  520.24  984.2 HEA  62.3 DBTDL0.125 0.200 PE-23 4 HDI/2 C-2050/2 HEMA HDI  65.47 C-2050  383.11  984.2HEMA  51.42 DBTDL 0.125 0.200 PE-24 4 MDI/2 C-2050/2 HEMA MDI  91.56C-2050  360.11  984.2 HEMA  48.33 DBTDL 0.125 0.200 PE-25 4 IPDI/2C-1090/2 HEMA IPDI 131.81 C-1090  289.85  488.67 HEMA  78.35 DBTDL 0.1250.200 PE-26 4 IPDI/2 C-2015N/2 HEMA IPDI  83.44 C-2015N  366.97  977.35HEMA  49.60 DBTDL 0.125 0.200 PE-27 4 IPDI/2 C-2050/2 HEMA IPDI 117.46C-2050  520.24  984.2 HEMA  69.82 BiN 0.177 0.283 PE-28 4 IPDI/2 XPC2613/2 HEMA IPDI  82.91 XP C2613  373.11 1000 HEMA  49.29 DBTDL 0.1250.200 PE-29 4 IPDI/2 C 7203/2 HEMA IPDI  81.08 C 7203  370.73 1016.12HEMA  48.19 DBTDL 0.125 0.200 PE-30 4 IPDI/1.5 C-3090/2.5 HEMA IPDI 74.20 C-3090  370.67 1480.21 HEMA  55.13 DBTDL 0.125 0.200 PE-31 4IPDI/1 C-3090/3 HEMA IPDI  95.75 C-3090  318.88 1480.21 HEMA  85.37DBTDL 0.125 0.200 PE-32 4 IPDI/2 C-2050/2 HEMA IPDI 265.57 C-2050 1176.6 984.2 HEMA 157.86 BiN 0.400 0.640 PE-33 IPDI/HEMA IPDI 319.8 — — — HEMA380.20 BiN 0.175 0.280 PE-34 4 IPDI/2 C-2050/2 HEMA IPDI  83.01 C-2050 367.65  984.2 HEMA  49.34 XK-672 0.125 0.200 PE-35 4 IPDI/2 C-2050/2HEMA IPDI  83.01 C-2050  367.65  984.2 HEMA  49.34 XK-672 0.125 0.200PE-36 4 IPDI/2 C-2050/2 HEMA IPDI  83.01 C-2050  367.65  984.2 HEMA 49.34 XK-672 0.125 0.200 PE-37 4 IPDI/2 C-2090/2 HEMA IPDI 125.16C-2090  550.45  977.35 HEMA  74.40 XK-672 0.125 0.200 PE-38 4 IPDI/2C-3090/2 HEMA IPDI  90.85 C-3090  605.15 1480.21 HEMA  54.00 XK-6720.125 0.200 PE-39 4 IPDI/2.5 C-2090/1.5 HEMA IPDI 108.02 C-2090  593.83 977.35 HEMA  48.15 XK-672 0.125 0.200 PE-40 4 IPDI/3 C-2090/1 HEMA IPDI 95.00 C-2090  626.76  977.35 HEMA  28.24 XK-672 0.125 0.200 PE-41 4IPDI/2 C-1090/2 HEMA IPDI 117.78 C-1090  262.21  494.71 HEMA  70.01XK-672 0.113 0.180 PE-42 4 IPDI/2.5 C-1090/1.5 HEMA IPDI 106.42 C-1090 296.14  494.71 HEMA  47.44 XK-672 0.113 0.180 PE-43 4 IPDI/3 C-1090/1HEMA IPDI  97.06 C-1090  324.10  494.71 HEMA  28.85 XK-672 0.113 0.180PE-44 4 IPDI/2 C-2050/2 HEMA IPDI 248.55 C-2050 1100.80  984.2 HEMA150.65 XK-672 0.375 0.600 PE-45 4 IPDI/2 NL2030B/2 HEMA IPDI  97.35NL2030 B  442.80 1010.8 HEMA  59.86 XK-672 0.15 0.240 PE-46 4 IPDI/2NL2005B/2 HEMA IPDI  95.91 NL2005 B  445.11 1031.25 HEMA  58.98 XK-6720.15 0.240 PE-47 4 IPDI/2 NL2010DB/2 HEMA IPDI  98.25 NL2010 DB  441.34 998.22 HEMA  60.41 XK-672 0.15 0.240 PE-48 H12MDI/HEMA H12MDI 310.25HEMA 324.73 XK-672 0.159 0.254 PE-49 4 IPDI/2 C-3090/1 HEMA/1 IPDI 71.35 C-3090  470.32 1464.75 HEMA/G- 22.04/36.28 XK-672 0.159 0.254G-AC-MAC Ac-MAC PE-50 4 IPDI/2 C-3090/2 IPDI  69.70 C-3090  459.421467.75 G-AC-MAC  72.49 XK-672 0.159 0.254 G-AC-MAC * add diol over 1.5h

Determination of HEMA-IPDI-HEMA Oligomer Concentration.

Determination of a concentration of HEMA-IPDI-HEMA oligomer wasperformed by liquid chromatography-mass spectrometry (LC/MS) on anAgilent 1260 Infinity Series liquid chromatography system (AgilentTechnologies, Waldbronn, Germany) using an Agilent Poroshell 120SB-C82.1 mm×50 mm 2.7 micrometer column eluted at 40° C. with a flowrate of 0.5 mL per minute. 2 microliter samples were injected and elutedwith a linear gradient as described below. The water was Omnisolv HPLCgrade from EMD Millipore, a part of Merck KGaA. The re-equilibrationtime between experiments was 5 minutes. Detection was with an Agilent6130 Quadrupole LC/MS detector with electrospray ionization. Samplequantification was done by integration of the chromatographic peakdetected at 500.3 m/z (M-NH₄ ⁺). Mass spectrometer parameters were inatmospheric pressure ionization-electrospray (API-ES) mode: capillaryvoltage 4 kV, nebulizer gas pressure 50 psig (345 kPa gauge), drying gasflow rate 10 liters per minute, drying gas temperature 300° C.

TABLE 3 Solvent elution gradient Solvent Time (min)  6 mM ammoniumformate in water 0  6 mM ammonium formate in 98% acetonitrile/2% water 3 6 mM ammonium formate in 98% acetonitrile/2% water 5 89% acetonitrile10% tetrahydrofuran 1% formic acid 6 89% acetonitrile 10%tetrahydrofuran 1% formic acid 8  6 mM ammonium formate in water 9

Calibration samples were prepared by dissolution of 0.1009 g of materialpolyurethane acrylate PE-33 in a 100 mL volumetric flask using ethylacetate. This solution was then diluted 1 mL into a 100 mL volumetricflask using acetonitrile to produce dilution 1. Dilution 1 was furtherdiluted to ˜2.02, 0.505, 0.101 and 0.0121 ppm concentrations inacetonitrile and filtered through 0.22 micron PTFE syringe filters(Fisher Brand, Thermo Fisher Scientific, Hampton, N.H.). The calibrationcurve was linear from 2.02-0.0121 ppm. Calibrations were performeddirectly preceding analytical samples.

Analytical samples were prepared by dissolution of 0.1-0.3 g of materialin a 100 mL volumetric flask using ethyl acetate. This solution was thendiluted 1 mL into a 100 mL volumetric flask using acetonitrile toproduce dilution 1. Dilution 1 was filtered through 0.22 micron PTFEsyringe filters (Fisher Brand) and analyzed as discussed above. Theresults for each sample are shown in Table 4 below.

TABLE 4 % HEMA-IDPI-HEMA in polymer (does not IPDI:Polyol:HEMA includeIBOMA Sample Polyol Catalyst eq ratio diluent if present) PE-13 C-3090DBTDL 4:2:2  5.0% PE-30 C-3090 DBTDL 4:1.5:2.5 11.1% PE-31 C-3090 DBTDL4:1:3 20.7% PE-37 C-2090 XK-672 4:2:2  5.4% PE-38 C-3090 XK-672 4:2:2 3.8% PE-7 C-2050 DBTDL 4:2:2  5.6% PE-9 C-2050 DBTDL 4:2:2  5.5% PE-32C-2050 BiN 4:2:2  5.7% PE-25 C-1090 DBTDL 4:2:2  8.6% PE-39 C-2090XK-672 4:2.5:1.5  3.0% PE-40 C-2090 XK-672 4:3:1  0.3% PE-41 C-1090XK-672 4:2:2  7.5% PE-42 C-1090 XK-672 4:2.5:1.5  1.8% PE-43 C-1090XK-672 4:3:1  0.1% PE-44 C-2050 XK-672 4:2:2  5.0%

General Procedure for Formulation Preparation

Formulations were prepared by weighing the components (indicated inTables 5-17) in an amber jar, followed by rolling on a roller (havingthe trade designation “OLDE MIDWAY PRO18” and manufactured by OldeMidway) at 60° C. until mixed.

TABLE 5 Example formulations (amounts in parts by weight) Component EX-1EX-2 EX-3 EX-4 EX-5 EX-6 PE-41 50 PE-42 50 PE-43 50 PE-37 50 PE-39 50PE-40 50 IBOMA 50 50 50 50 50 50 TPO 2 2 2 2 2 2

TABLE 6 Example formulations (amounts in parts by weight) EX- EX- EX-EX- EX- EX- EX- EX- Component 7 8 9 10 11 12 13 14 PE-19 50 PE-7 50PE-22 50 PE-20 50 PE-21 50 PE-23 50 PE-24 50 PE-6 50 IBOMA 50 50 50 5050 50 50 50 TPO 2 2 2 2 2 2 2 2 BHT 0.025

TABLE 7 Example formulations (amounts in parts by weight) ComponentEX-15 EX-16 EX-17 EX-18 EX-19 PE-38 50 PE-31 50 PE-26 50 PE-8 50 PE-2850 IBOMA 50 50 50 50 50 TPO 2 2 2 2 2

TABLE 8 Example formulations (amounts in parts by weight) ComponentEX-20 EX-21 EX-22 EX-23 EX-24 EX-25 PE-25 25 18 10 15 PE-13 25 32 25 35PE-19 25 PE-26 40 PE-30 40 PE-14 10 AdMA 50 IBOMA 50 50 50 50 50 TPO 2 22 2 2 2

TABLE 9 Example formulations (amounts in parts by weight) ComponentEX-26 EX-27 EX-28 EX-29 EX-30 PE-13 45 40 PE-30 47.5 PE-32 47.5 PE-33 510 2.5 2.5 5 PE-11 45 IBOMA 50 50 50 50 50 TPO 2 2 2 2 2

TABLE 10 Example formulations (amounts in parts by weight) ComponentEX-31 EX-32 EX-33 EX-34 EX-35 EX-36 PE-5 40 40 40 40 PE-7 40 40 PE-9 10PE-10 10 PE-11 10 PE-12 10 PE-15 10 PE-16 10 IBOMA 50 50 50 50 50 50 TPO2 2 2 2 2 2

TABLE 11 Example formulations (amounts in parts by weight) ComponentEX-37 EX-38 EX-39 EX-40 PE-7 40 40 PE-5 45 PE-32 50 C-590 diol 10 MAC-2050 diol 10 MA DDDMA 5 HDDMA 10 IBOMA 50 50 50 40 TPO 2 2 2 2

TABLE 12 Example formulations (amounts in parts by weight) Compo- EX-EX- EX- EX- EX- EX- EX- EX- EX- nents 41 42 43 44 45 46 47 48 49 PE-1950 PE-5 40 60 PE-32 50 50 50 50 PE-14 45 PE-33 5 PE-7 50 IBOMA 60 40 50DiCPMA 50 50 AdMA 50 tBuCHMA 50 CHMA 50 TMCHMA 50 TPO 2 2 2 2 2 2 2 2 2

TABLE 13 Example formulations (amounts in parts by weight) ComponentsEX-50 EX-51 EX-52 EX-53 EX-54 EX-55 PE-19 50 PE-22 50 PE-27 50 PE-34 50PE-35 50 PE-36 50 IBOMA 50 50 50 50 IBOA 50 50 TPO 2 2 2 2 2 2

TABLE 14 Example formulations (amounts in parts by weight) EX- EX- EX-EX- EX- EX- EX- Components 79 80 81 82 83 84 85 PE-13 45 PE-32 50 PE-4550 PE-46 50 PE-47 50 PE-48 5 PE-49 50 PE-50 50 tBuCHMA 50 IBOMA 50 50 5050 50 50 TPO 2 2 2 2 2 2 2

TABLE 15 Example formulations (amounts in parts by weight) ComponentsEX-87 EX-88 EX-89 Exothane 10 10 PE-44 50 50 40 IBOMA 40 30 50 HEMA 1020 TPO 2 2 2

TABLE 16 Comparative example formulations (amounts in parts by weight)Components CE-1 CE-2 CE-3 CE-4 CE-5 CE-6 PE-32 50 50 50 50 Exothane 1030 50 CEA 50 NVP 20 IBOMA 50 EHMA 50 PEMA 50 PEG600DMA 50 THFMA 50 TPO 22 2 2 2 2

TABLE 17 Comparative example formulations (amounts in parts by weight)Components CE-7 CE-8 CE-9 CE-10 CE-11 CE-12 Exothane 108 50 PE-18 50PE-17 50 PE-5 30 70 PE-4 50 IBOMA 50 50 50 70 30 50 TPO 2 2 2 2 2 2 BHT0.025 0.025 0.025

Polymer/Oligomer Molecular Weight Characterization Method:

The molecular weights of the oligomers and the polymers werecharacterized using gel permeation chromatography (GPC). The GPCequipment consisted of an e2695 Separation Module and a 2414 dRIdetector, both from Waters Corporation (Milford, Mass.). It was operatedat a flow rate of 0.6 mL/min using tetrahydrofuran as the eluent. TheGPC column was a HSPgel HR MB-M column also from Waters Corporation. Thecolumn compartment and differential refractive index detector were setto 35° C. The molecular weight standards were EasiVial PMMA from AgilentTechnologies (The M_(p) values of the PMMA molecular weight standardsused in the calibration curve ranged from 550 D to 1,568,000 g/mol.) Therelative number average molecular weight (Mn) and weight averagemolecular weight (Mn) of selected oligomers/polymers are tabulated belowin Table 18, in kiloDaltons (kD):

TABLE 18 Sample Mn (kD) Mw (kD) Polydispersity PE-6 4.3 18.1 4.2 PE-73.5 12.1 3.4 PE-8 3.5 12.4 3.5 PE-9 3.0 7.5 2.5 PE-10 3.1 7.4 2.4 PE-113.1 8.1 2.6 PE-12 3.3 8.7 2.6 PE-13 4.3 17.9 4.1 PE-14 4.5 11.5 2.6PE-17 1.6 6.3 4.1 PE-18 3.8 12.9 3.4 PE-19 2.1 8.9 4.3 PE-20 5.0 16.43.3 PE-21 3.7 14.3 3.9 PE-22 3.1 11.6 3.7 PE-23 3.9 17.0 4.4 PE-24 3.414.0 4.1 PE-25 2.0 5.6 2.8 PE-26 2.9 12.8 4.3 PE-27 3.3 14.0 4.3 PE-282.8 12.3 4.4 PE-29 3.6 11.5 3.2 PE-30 2.9 12.9 4.4 PE-31 2.0 9.8 4.9PE-32 3.9 12.1 3.1 PE-33 4.1 14.4 3.5 PE-35 3.5 12.9 3.7 PE-36 3.6 12.03.4 PE-39 7.4 21.8 3.0 PE-40 11.3 30.5 2.7 PE-41 2.8 6.3 2.2 PE-42 3.99.1 2.3 PE-43 6.3 15.8 2.5 PE-44 4.6 12.8 2.8 PE-45 14.3 24.6 1.7 PE-4615.6 25.8 1.8 PE-47 18.3 32.1 1.8

General Procedure of Formulation Casting and Curing

Each formulation indicated in Tables 5-17 was poured into a siliconedogbone mold (Type V mold of 1 mm thickness, ASTM D638-14) for preparingtensile specimens, and a rectangular mold of dimensions (9.4 mm×25.4mm×1 mm) for DMA 3-point bend test specimens. A 2 mil (0.05 mm)polyethylene terephthalate (PET) release liner (obtained under the tradedesignation “SCOTCHPAK” from 3M Company (St. Paul, Minn.)) was rolled onthe filled mold, and the filled mold along with the liner was placedbetween two glass plates held by binder clips. The formulation was curedunder a Asiga Pico Flash post-curing chamber (obtained from Asiga USA,Anaheim Hills, Calif.) for 30 minutes. The specimens were removed fromthe mold followed by additional light exposure for 30 minutes using theAsiga Pico Flash post-curing chamber. Specimens were then kept in anoven set at 100° C. for 30 minutes. The dogbone specimens wereconditioned in Phosphate-buffered saline (PBS, 1×, pH=7.4) for 24 hoursat 37° C. The DMA 3-point bend test specimens were conditioned inde-ionized (DI) water for 48 hours at room temperature.

General Procedure for Determination of Loss Modulus and Tan Delta UsingDynamic Mechanical Analysis

Dynamic mechanical analysis (DMA) was performed on rectangular curedsamples (approximately 25.4 mm×9.4 mm×1 mm) using a TA Instruments modelQ800 dynamic mechanical analyzer (TA Instruments (Newcastle, Del.))using a tension clamp in controlled strain mode, 0.2% strain, 0.02 Npreload force, 125% force track, 1 Hz. Temperature was swept at a rateof 2° C./min from −40° C. to 200° C. Samples were immersed in deionizedwater at 37° C. for least 24 hours, at which time the samples were fullysaturated with water prior to testing and tested immediately afterremoval from water.

TABLE 19 Measured physical properties of samples. Peak loss Peak Tandelta Sample Resin 1 Resin 2 modulus (° C.) (° C.) EX-8 PE-7 IBOMA 2 121EX-47 PE-32 CHMA 0 73 CE-12 PE-4 IBOMA 44 129 EX-44 PE-32 AdMA 5 117CE-1 PE-32 PEMA −7 31 CE-4 PE-32 EHMA −21 26 EX-51 PE-22 IBOA −14 67CE-6 Exothane 10 IBOMA 31 124

Additive Manufacturing of Formulated Resins

Unless otherwise noted, all 3D-printed examples were manufactured eitheron an Asiga Pico 2 HD or Asiga Max, a vat polymerization 3D printeravailable from Asiga USA, Anaheim Hills, Calif. Each formulation listedin Tables 20-23 was photopolymerized on an Asiga 3D printer with a LEDlight source of 385 nm. Tensile test bars of Type V according to ASTMD638-14 (2014) and DMA 3-point bend test specimens were manufactured.The resin bath of the printer was heated to 35-50° C. beforephotopolymerization to reduce the viscosity to be able to manufacturethe tensile test bars. The following settings were used for theprinting: slice thickness=50 μm; burn in layers=1; separationvelocity=1.5 mm/s, separation distance=10 mm, approach velocity=1.5mm/s. On the Asiga Pico 2 HD, 1 slide per layer was used at a speed of 7mm/min. In addition, Table 24 describes the printer type, and theexposure time, burn-in time, and temperature used for printing theformulations indicated in Tables 20-23. The printed parts were washedusing propylene carbonate followed by isopropanol to remove unreactedresin. The printed part was then post-cured using Asiga Pico Flashpost-curing chamber for 90 minutes on each side followed by heating inan oven at 100° C. for 30 minutes. The dogbone specimens wereconditioned in phosphate-buffered saline (PBS, 1×, pH=7.4) for 24 hoursat 37° C. The DMA 3-point bend test specimens were conditioned in DIwater for 48 hours at room temperature.

TABLE 20 Example formulations for additive manufacturing (amounts inparts by weight) Components EX-56 EX-57 EX-58 EX-59 EX-60 PE-43 50 PE-4450 50 50 PE-32 50 IBOMA 50 50 50 50 50 TPO 2 2 0.5 0.5 BHT 0.025 0.0250.025 0.025 0.025 Omnirad 379 0.75 NapA 0.025 0.025 0.1 0.0175 Tinuvin326 0.025

TABLE 21 Example formulations for additive manufacturing (amounts inparts by weight) Compo- EX- EX- EX- EX- EX- EX- EX- nents 61 62 63 64 6566 67 PE-7 47 PE-5 44 PE-6 50 PE-37 50 PE-25 25 PE-13 25 25 20 PE-19 2530 IBOMA 53 56 50 50 50 50 50 TPO  2  2  2  2  2  2  2 BHT  0.025  0.025 0.025  0.025  0.025  0.025  0.025 NapA  0.025  0.025  0.025  0.025 0.025  0.025  0.025

TABLE 22 Example formulations for additive manufacturing (amounts inparts by weight) Compo- EX- EX- EX- EX- EX- EX- EX- nents 68 69 70 71 7273 74 PE-5 PE-19 50 PE-44 49.42 45.22 44.69 44.16 39.96 PE-33  5.58 9.78  7.81  5.84  10.04  5 PE-13 45 IBOMA 40 45 45 47.5 50 50 50 HDD-10 MA TPO  0.5  2  2  2  2  2  2 BHT  0.025  0.025  0.025  0.025  0.025 0.025  0.025 NapA  0.1  0.025  0.025  0.025  0.025  0.025  0.025

TABLE 23 Example formulations for additive manufacturing (amounts inparts by weight) Components EX-75 EX-76 EX-77 EX-78 EX-86 PE-19 50 PE-3250 PE-13 50 PE-30 40 PE-14 10 PE-47 50 DiCPMA 50 AdMA 50 50 50 IBOMA 50TPO 2 2 2 2 2 BHT 0.025 0.025 0.025 0.025 0.025 NapA 0.025 0.025 0.0250.025 Tinuvin 326 0.025

TABLE 24 Additive manufacturing conditions. Exposure Burn-in TemperatureExample Printer Time (sec) Time (sec) (° C.) EX-56 Asiga Pico 2 HD 2.2515 50 EX-57 Asiga Max 3 10 40 EX-58 Asiga Max 5 10 40 EX-59 Asiga Pico 2HD 3.75 20 50 EX-60 Asiga Max 4.5 10 40 EX-61 Asiga Pico 2 HD 2 8 50EX-62 Asiga Pico 2 HD 2.5 8 50 EX-63 Asiga Max 2.5 10 40 EX-64 AsigaPico 2 HD 2 8 50 EX-65 Asiga Pico 2 HD 2 8 50 EX-66 Asiga Max 3 10 40EX-67 Asiga Pico 2 HD 2 8 50 EX-68 Asiga Pico 2 HD 2 8 50 EX-69 AsigaMax 3 10 40 EX-70 Asiga Max 3 10 40 EX-71 Asiga Max 3 10 40 EX-72 AsigaMax 3 10 40 EX-73 Asiga Max 3 10 40 EX-74 Asiga Pico 2 HD 2 8 50 EX-75Asiga Pico 2 HD 2 8 50 EX-76 Asiga Pico 2 HD 2 8 50 EX-77 Asiga Pico 2HD 2 8 50 EX-78 Asiga Pico 2 HD 2 8 50 EX-86 Asiga Max 5 10 40

General Procedure for Tensile Testing

PBS conditioned dogbones were tested on an Instron 5944 (Instron,Norwood, Mass.) with a 500 N load cell. The test speed was 5 mm/minuteand the initial grip separation was 1 inch (2.5 cm). The gauge lengthwas set to 1 inch (2.5 cm). Five replicate samples for each formulationwere tested, and the average value are reported. The tensile strength atyield was determined according to ASTM D638-14 (2014) and shown in Table25 and Table 26 below. For specimens that did not yield, maximum tensilestrength was determined. Elongation at break was determined from thecrosshead movement of the grips.

General Procedure for the Determination of Relaxation Modulus UsingDynamic Mechanical Analysis

Rectangular specimens were water conditioned by soaking in deionizedwater for 48 hours at room temperature at 22 to 25° C. and were testedin a TA Q800 DMA equipped with a submersion 3-point bending clamp. Thewater conditioned rectangular specimens were placed in water filledsubmersion fixture. The specimens were equilibrated for 10 minutes at37° C., followed by applying a 2% strain. Relaxation modulus wasmeasured for 30 minutes using TA Advantage software, and is reported inTables 25 and 26.

TABLE 25 Yield strength, elongation and relaxation modulus of castformulations. Percent Loss of Initial Relaxation Relaxation Strength atElongation Relaxation Modulus at Modulus Yield at Break Modulus 30Minutes After Sample (MPa) (%) (MPa) (MPa) 30 Minutes CE-1 9.3* 167.5N.M1 N.M1 N.M1 CE-2 8.6* 181.1 N.M1 N.M1 N.M1 CE-3 1.3* 5.8 N.M1 N.M1N.M1 CE-4 2.9* 87.7 N.M1 N.M1 N.M1 CE-5 1.2* 32.0 N.M2 N.M2 N.M2 CE-646.9 2.9 1662.0 712.5 57.1 CE-7 26.1 9.3 1027.0 265.8 74.1 CE-8 15.2122.7 401.5 51.2 87.2 CE-9 15.7* 1.0 N.M2 N.M2 N.M2 CE-10 29.3* 1.7 N.M2N.M2 N.M2 CE-11 25.2* 130.9 106.2 17.2 83.8 CE-12 64.8* 2.8 2829.01859.0 34.3 EX-1 56.2 7.6 1442.0 720.9 50.0 EX-2 42.0 12.9 798.4 313.460.7 EX-3 28.7 84.2 594.3 212.9 64.2 EX-4 30.7 38.9 794.8 312.4 60.7EX-5 22.1 80.8 540.8 214.2 60.4 EX-6 17.6 113.9 498.5 198.8 60.1 EX-739.1 17.1 1213.0 545.1 55.1 EX-42 39.7 16.5 1096.0 557.9 49.1 EX-43 17.492.7 438.1 84.1 80.8 EX-9 22.2 36.4 632.3 174.3 72.4 EX-10 20.2 90.3565.6 182.2 67.8 EX-11 22.5 70.0 740.8 219.8 70.3 EX-12 14.7 75.8 500.1143.2 71.4 EX-13 27.7 46.3 922.2 365.7 60.3 EX-14 28.5 46.7 867.1 380.856.1 EX-15 23.1 90.7 655.8 258.5 60.6 EX-16 38.3 12.2 949.6 458.8 51.7EX-50 17.2 64.1 263.4 17.6 93.3 EX-17 26.8 44.7 763.1 219.6 71.2 EX-1821.1 65.5 498.0 147.6 70.4 EX-19 23.5 15.5 772.8 295.0 61.8 EX-20 35.525.1 1020.0 434.7 57.4 EX-21 33.2 30.9 977.7 391.6 59.9 EX-24 27.3 66.6780.3 287.9 63.1 EX-23 32.9 54.9 1173.0 397.1 66.1 EX-22 30.4 48.0 859.1368.4 57.1 EX-44 33.3 27.5 837.5 325.0 61.2 EX-45 21.5 67.9 369.7 71.980.6 EX-41 32.8 35.2 808.1 229.3 71.6 EX-46 16.6 66.6 345.8 73.6 78.7EX-47 14.0 125.6 169.0 13.9 91.8 EX-29 28.4 37.8 746.3 267.7 64.1 EX-2829.0 34.7 879.7 362.3 58.8 EX-26 30.8 47.5 824.4 366.9 55.4 EX-27 37.812.5 985.1 476.6 51.6 EX-31 24.1 63.7 612.6 201.5 67.1 EX-32 24.7 58.1602.8 197.0 67.3 EX-33 26.8 53.9 691.4 246.8 64.3 EX-34 26.3 57.1 577.6172.8 70.1 EX-35 27.8 53.0 698.4 220.0 68.5 EX-36 34.4 28.4 882.6 327.262.9 EX-25 28.7 56.3 738.1 285.1 61.4 EX-30 23.3 51.0 458.0 109.0 76.2EX-48 24.1 28.2 591.9 177.3 70.0 EX-37 30.0 29.2 691.0 251.7 63.6 EX-3824.6 66.0 640.6 196.0 69.4 EX-39 32.8 30.5 916.3 410.2 55.2 EX-40 21.366.2 570.5 156.7 72.5 EX-8 26.9 54.4 765.0 264.7 65.4 EX-49 22.2* 75.5261.1 56.1 78.5 EX-52 27.8 63.4 749.0 282.4 62.3 EX-53 25.1 53.0 636.2236.1 62.9 EX-54 27.9 53.5 761.9 264.1 65.3 EX-55 26.1 49.9 746.3 258.665.3 EX-51 18.8* 101.0 121.1 20.5 83.1 EX-79 35.0 14.9 1051.0 457.8 56.4EX-80 19.6* 28.5 486.0 190.0 60.9 EX-81 30.1 33.3 891.0 369.7 58.5 EX-8232.7 24.2 924.5 441.3 52.3 EX-83 26.3 50.2 741.5 335.4 54.8 EX-84 29.730.4 649.4 311.8 52.0 EX-85 16.6 66.6 345.8 73.6 78.7 EX-87 26.6 66.6486.2 74.5 84.7 EX-88 16.6 91.9 316.7 21.7 93.14 EX-89 36 23.3 926.9346.3 62.64 N.M1. Not measured since these samples were very flexibleand soft, and couldn't be successfully clamped for DMA testing. N.M2.Not measured since these specimens were very brittle. *maximum tensilestrength is reported for specimens that did not yield.

TABLE 26 Yield strength, elongation and relaxation modulus of printedformulations. Percent Loss of Initial Relaxation Relaxation StrengthElongation Relaxation Modulus at Modulus at Yield at Break Modulus 30Minutes After Sample (MPa) (%) (MPa) (MPa) 30 Minutes EX-56 24.1 91.2536.0 187.6 65.0 EX-57 25.0 103.0 722.5 252.7 65.0 EX-58 21.6 83.8 666.1227.7 65.8 EX-59 21.9 126.4 612.7 194.4 68.3 EX-60 23.8 93.2 675.7 226.566.5 EX-61 28.3 96.7 857.5 325.0 62.1 EX-62 36.5 24.7 1175.0 460.1 60.8EX-63 29.0 76.4 710.8 277.7 60.9 EX-64 27.1 126.0 805.2 303.4 62.3 EX-6531.3 70.4 978.2 383.7 60.8 EX-66 25.0 111.1 406.3 157.2 61.3 EX-67 29.475.0 879.5 368.8 58.1 EX-68 24.2 32.8 620.9 211.2 66.0 EX-69 26.7 65.5696.4 249.4 64.2 EX-70 35.6 41.2 1007.0 436.1 56.7 EX-71 35.7 43.5 983.0441.2 55.1 EX-72 36.6 42.9 925.3 413.6 55.3 EX-73 43.7 20.6 1199.0 564.852.9 EX-74 23.8 98.7 649.0 261.8 59.7 EX-75 28.9 74.7 800.3 249.1 68.9EX-76 30.3 88.7 789.4 288.3 63.5 EX-77 22.7 144.9 738.1 285.1 61.4 EX-7827.6 95.9 707.1 265.0 62.5 EX-86 28.9 28.3 715.4 322.7 54.9Additive Manufacturing of Aligner Articles from the Formulated Resin

The formulation of EX-57 was photopolymerized on the Asiga Max printerwith a LED light source of 385 nm. A stereolithography file format (STLfile) of the aligner was loaded into the Asiga Composer software, andsupport structures were generated. The resin bath of the printer washeated to 40° C. before photopolymerization to reduce the viscosity tobe able to manufacture the article. The following settings were used forthe printing: slice thickness=50 μm; burn in layers=1; separationvelocity=1.5 mm/min, burn-in exposure time=10 sec; exposure time=3 sec.The printed part was washed using propylene carbonate followed byisopropanol to remove unreacted resin. The printed specimen was thenpost-cured using an Asiga Pico Flash post-curing chamber for 90 minuteson each side. The photopolymerized aligners fit the models, showingprecision of the additive manufacture part. The aligner had acceptablestrength and flexibility.

Test Procedure for Gravimetric Analysis of Extractable from PrintedArticles

Articles shaped as a continuous 5-tooth row (30.4 mm×9.24 mm×8.17 mm)using formulations of EX-57 and EX-58 were printed and post processedaccording to the procedure described above. The thickness of the articlewas 0.49 mm. 3×5-tooth articles (total surface area of 45 cm²) wereplaced in a 40 mL glass vial and weighed. 15 mL of solvent (eitherheptane or 5% ethanol/Milli-Q water) was added to the vial, with one 15mL blank (vial without articles) for each solvent. The vials werecovered with TEFLON caps, and the samples were kept at 37° C. for 24hours while shaking at 80 RPM in a LabLine Bench top incubated shakerModel 4628. The samples were allowed to cool before transferring theextraction solution to a new 20 mL glass vial. A 5 mL aliquot wastransferred to a preweighed 8 mL glass vial and set to evaporate under anitrogen purge. The vials were weighed once the solvent dried off, untila constant weight was reached. % Residue was calculated using thefollowing formula shown below. The test was completed in triplicates,all run at the same time, and result shown is the average of the threereplicates.

${\%\mspace{14mu}{Residue}} = {\left\lbrack \frac{\left( {{{Vial}\mspace{14mu}{after}\mspace{14mu}{{evaporation}(g)}} - {{Vial}\mspace{14mu}{{tare}(g)}}} \right)*15\mspace{14mu}{mL}\mspace{14mu}{solvent}}{{Mass}\mspace{14mu}{of}\mspace{14mu}{article}\mspace{14mu}(g)*5\mspace{14mu}{mL}\mspace{14mu}{solvent}\mspace{14mu}{analyzed}} \right\rbrack*100}$

TABLE 27 % Extractable % Extractable in Sample in Heptane 5% EtOH/H₂OEX-57 0.444 0.129 EX-58 0.280 0.072

All of the patents and patent applications mentioned above are herebyexpressly incorporated by reference. The embodiments described above areillustrative of the present invention and other constructions are alsopossible. Accordingly, the present invention should not be deemedlimited to the embodiments described in detail above and shown in theaccompanying drawings, but instead only by a fair scope of the claimsthat follow along with their equivalents.

1. A compound of Formula (V):